| 释义 |
▪ I. parity1|ˈpærɪtɪ|
[ad. L. paritās equality, f. par equal. Cf. F. parité (14th c. in Hatz.-Darm.).]
1. a. The state or condition of being equal, or on a level; equality.
1613R. Cawdrey Table Alph. (ed. 3), Paritie, equalitie, likenesse. 16..Webster & Rowley Cure for Cuckold i. i, Equality in birth, parity in years. c1656Bramhall Replic. v. 190 For the clearing of which point, I shewed that there was a parity of power among the Apostles. 1783W. F. Martyn Geog. Mag. II. 326 Men and women [in marriage] are obliged to pay a proper regard to the parity of years. 1842Grove Corr. Phys. Forces 101 The bodies in which this parity of force has been discovered..are small compared with the exceptions.
b. A state in which two countries potentially hostile to one another have equal strategic resources, used spec. of the capacities in nuclear weapons of the U.S. and the U.S.S.R.
1955Bull. Atomic Sci. Mar. 100/2 To try to achieve parity in conventional weapons would mean such a regimentation of our industry and manpower that we would lose the freedom we seek to preserve. 1965H. Kahn On Escalation 295 The term ‘parity’ is shorthand for ‘nuclear parity’ or ‘strategic parity’. Parity exists when neither side obtains any important strategic technical advantages..from its central war forces. 1971Human World Nov. 20 In the last five or six years the Russians have achieved nuclear-missile parity with the United States.
c. In phr. parity of esteem, the state or condition of being regarded as equal, used spec. of the status of administratively comparable educational institutions.
1961D. Jenkins Equality & Excellence vi. 112 The authors of the 1944 [Education] Act..enunciated their principle..that there should be ‘parity of esteem’ for all forms of secondary education. 1961Guardian 3 Apr. 3/2 The training colleges must aim high... Parity of esteem with the universities must be earned. 1966D. Jenkins Educated Society ii. 63 There has to be ‘parity of esteem’ as between the various sections of the community. 1966Rep. Comm. Inquiry Univ. Oxf. I. 117 We are convinced that undergraduate and postgraduate education should enjoy parity of esteem. 1974Listener 23 May 661/3 If they [sc. polytechnics] could accept the challenge that they can offer a different kind of degree from well-established universities, they might get something like parity of esteem.
2. Equality of rank or status, social, political, or ecclesiastical; esp., equality among the members, or among the ministers, of a church.
1572in Neal Hist. Purit. (1732) I. 284 There ought to be a Parity among the ministers in the Church. 1593Bilson Govt. Christ's Ch. 413 What conflictes and uproares your paritie of Presbyters will breede. 1642Chas. I Answ. 19 Prop. 22 The Common people..grow weary of Journey⁓work, and set up for themselves, call Parity and Independence, Liberty. 1709Hearne Collect. 5 Mar. (O.H.S.) II. 173 To..introduce Presbyterian parity..among our Clergy. 1841D'Israeli Amen. Lit. (1867) 442 With the disciples of parity, a free election..was a first state principle. 1903F. W. Maitland in Camb. Mod. Hist. II. xvi. 594 A call for ‘parity’, for an equality among all the ministers of God's Word, and consequently for an abolition of all ‘prelacy’.
3. Equality of nature, character, or tendency; likeness, similarity, analogy; parallelism; as in parity of reason or reasoning. (Cf. L. pari ratione.)
1620Venner Via Recta iii. 55, I thinke that there is a neerer parity of nature betweene the flesh of Fallow-Deere, and of the Red. 1646P. Bulkeley Gospel Covt. i. 33 Argument..from the paritie and likenesse between the covenant of works, and the covenant of grace. 1652Needham tr. Selden's Mare Cl. 23 Truly there is a paritie of Reason also for this. 1692Bentley Boyle Lect. ix. 325 We may infer by parity of Argument. 1734Berkeley Hylas & Phil. (ed. 3) iii. Wks. 1871 I. 329 There is..no parity of case between Spirit and Matter. 1834Mudie Brit. Birds (1847) I. 172 By parity of reasoning that house on which the magpie perches is in no danger of falling.
4.
†a. Of numbers: The fact of being even and not odd; evenness. Obs.
a1619M. Fotherby Atheom. ii. x. §4 (1622) 308 It [unity] is not variable, by parity; or imparitie. 1646Sir T. Browne Pseud. Ep. 115 If we survey the totall set of animals, we may in their legs..observe an equality of length, and parity of numeration; that is, not any to have an odde leg.
b. The oddness or evenness of a number, or of the number characteristic of something.
1915P. A. MacMahon Combinatory Analysis I. iii. vi. 139 (heading) The parity of the greater index. 1949G. & R. C. James Math. Dict. 258/1 If two integers are both odd or both even they are said to have the same parity; if one is odd and the other even they are said to have different parity. 1960G. N. Lance Numerical Methods for High Speed Computers i. 10 The extended word should always have odd parity unless binary digits have been lost or gained during the transfer of the word from one part of the machine to another. 1966R. R. Arnold et al. Introd. Data Processing xiv. 268/2 Codes that use an odd number of bits are said to have an odd parity. Codes that use an even number of bits are said to have an even parity. 1971Hunter & Monk Algebra & Number Syst. ii. 28 Let us..say that b is related to a, when the positive integer b has the same parity as the positive integer a, that is when a and b are either both odd or both even. 1975J. Finkel Computer-Aided Experimentation xvii. 374 Parity is computed by adding the total number of ‘ones’ in a word. If the total is an even number and even parity is desired, the parity bit is stored as a ‘zero’.
c. Physics. The property of having or being a spatial wave function that remains the same (has even parity) or changes sign (has odd parity) when a change of sign is applied to the co-ordinates; also (charge parity, G-parity), the same property with respect to certain other symmetry operations (see quots. 1964, 1970); the value of the quantum number (eigenvalue) representing such a property (+1 for even parity, -1 for odd parity).
1939Physical Rev. LVI. 526/2 Only the selection rules for J and parity would remain valid (ΔJ = {pm}1 or 0, no change in parity allowed). 1953Ann. Rev. Nuclear Sci. II. 240 Means are available..for determining the angular momentum and parity change carried off by the emitted radiation. 1955R. D. Evans Atomic Nucleus iv. 174 The parity of an isolated system is a constant of its motion and cannot be changed by any internal processes. Only if radiation or a particle enters or leaves the system..can the parity change. 1956Canad. Jrnl. Physics XXXIV. 1110 There is..evidence for spin and parity assignment of ½(+) for the C15 ground state. 1957Times 11 Nov. 11/5 The launching of an Earth satellite is of less fundamental importance than..the failure of the law of parity conservation. 1964G. Källén Elem. Particle Physics xii. 316 We can describe the G-operation as a charge conjugation followed by a rotation [in isospin space] through the angle π around the i-axis. The eigenvalue of this operator is usually referred to as ‘G-parity’. Ibid. 317 G-parity is a conserved quantum number in all reactions involving strong interactions. 1968M. S. Livingston Particle Physics vii. 134 The parity of a wave function representing a system of particles includes the intrinsic parities of each of the individual particles and also depends on the relative angular momemtum of the several particles. 1969Observer 13 Apr. 2/6 Certain particles do not obey..the parity (or P) principle. This P principle says, in effect, that nature does not ‘know’ the difference between left and right. 1970Martin & Spearman Elem. Particle Theory v. 237 We define an operation C as the mapping of a physical system into another physical system in which each particle has been replaced by one with the opposite value of charge, baryon number, (lepton number) and strangeness... The eigenstates of C have eigenvalue either +1 or -1, that is they have either even or odd charge parity. 1973L. J. Tassie Physics Elem. Particles iii. 32 When discussing the parity of the π-, we assumed that the proton and the neutron have the same intrinsic parity. If we assume that the proton and the neutron have opposite intrinsic parities, then we find that the π- and the π0 have opposite intrinsic parities... We choose the parities for different charge states to give the simplest scheme.
5. Comm.
a. Equivalence in another currency; a standard of price expressed in another currency.
1886Wool Report 22 June, Public sales of wool..were held in Berlin..1800 bales..are reported to have been all sold at full London parity. 1886Times 7 July, Prices generally soon advanced above the parity of Saturday night's closing quotations in New York. 1894Ibid. 8 Dec. 5/2 The London parity will be about {pstlg}94·50.
b. = par n.1 2 b, 3 b.
1900Stock Market Report, Buying on days when the market is weak and below parity, and selling when prices are put above parity by the operations of local speculators.
c. An agreed price for agricultural produce, relative to other commodities.
1941Time 2 June (Air Exp. Ed.) 2/3 ‘Parity’ is a political concept which holds that the farmer should receive prices for his products which will give him a purchasing power (in terms of other commodities) equal to that which he had in the period 1909–14. 1977Askov (Minnesota) American 31 Mar. 1/2 The milk price support increase to 83 percent of parity will have a positive impact on Minnesota dairy farmers.
d. The value of one currency in terms of another or others, as agreed by the procedures of the International Monetary Fund, which became effective on 1 March 1947.
1945Ann. Reg. 1944 i. ii. 41 All transactions between the Fund and members were to be at par, and all transactions in member currencies at rates within an agreed percentage of parity. 1949Britannica Bk. of Year 254/2 Mexico temporarily suspended exchange transactions by the Central bank on July 22, 1948, pending the establishment of a new parity. Although the new parity had not been announced, the Bank of Mexico was authorized to engage in free market transactions. 1971Daily Tel. 10 May 14 The major countries agree..that if..the price of their own currency in relation to any other foreign exchange moves to more than 1 p.c. away from the fixed price (called parity), they will intervene. 1971Ibid. 11 May 1/3 The Swiss franc closed below its new parity of 4·08 to the dollar. 1976Shooting Times & Country Mag. 18–24 Nov. 28/2 Doubtless the parity of the pound sterling against other currencies is leaning..in favour of the visitor.
6. In Monetary parlance: Equality, as legal tender or money, between coins of one metal and coins of another in certain definite proportions of weight and fineness, fixed by law.
1895Spectator 2 Feb. 157 Convinced..that silver can be raised by legislation to a ‘parity’ with gold. 1900Ld. Aldenham Colloquy on Currency 280 The object..was to maintain the parity between Gold and Silver money... The parity which they have in the United States is a National parity between the coins, not between the metals... What I desire is International parity.
7. attrib. and Comb., as parity level, parity price; parity-preaching; parity bit Computers, a bit that is automatically made 1 or 0 so as to make the parity of the word or set containing it either odd or even, as previously determined; parity-canton, a canton in Switzerland where the Catholic and Protestant Churches are on an equal footing in their relations with the State; parity check Computers, a check on the correctness of a set of binary digits that involves ascertaining the parity of a number derived from the set in a predetermined way; so parity checking vbl. n.; parity digit Computers = parity bit above.
1957D. D. McCracken Digital Computer Programming xii. 151 A common system is to assign six bits to each character... The six bits and the parity bit are then recorded in a row, which requires a seven-channel tape. 1975J. Finkel Computer-Aided Experimentation xvii. 373 The parity bit is computed by the memory write hardware before storing a word. When a word is fetched from storage the parity bit is recomputed, and if it does not agree with the parity bit appended to the word an interrupt is issued.
1899Westm. Gaz. 27 July 3/3 In the ‘Parity-Cantons’ of the Swiss Confederation, where two Landeskirchen are established—a Catholic and an Evangelical Church.
1950R. W. Hamming in Bell Syst. Techn. Jrnl. XXIX. 150 The type of check used..will be called a parity check. The above was an even parity check; had we used an odd number of 1's to determine the setting of the check position it would have been an odd parity check. 1958IRE Trans. Electronic Computers VII. 207/1 If the specified number of ONE digits is even the parity check digit is a zero. If the number of ONE digits is odd the parity check digit is a one. 1970N. R. Scott Electronic Computer Technol. v. 220 ‘Digital’ parity checks..depend upon the digits of the number and not upon the significance attached to the digits by virtue of their position... The numerical parity check..is a function of the number represented by the digits but not a function of the digits themselves. 1972Computers & Humanities VI. 149 One channel is reserved for the internal control, the parity check.
1958IRE Trans. Electronic Computers VII. 207/1 Parity checking usually is defined for the binary system in terms of the odd or evenness of the number of ONE digits in a specified block of binary digits. 1966R. R. Arnold et al. Introd. Data Processing xiv. 268/1 Parity checking is a built-in self-checking feature utilized in most magnetic tape as well as paper tape coding methods.
1954Computers & Automation Dec. 18/1 Parity check, use of a digit (called the ‘parity digit’) carried along as a check. 1959S. H. Hollingdale High Speed Computing ii. 27 Some computers are designed to deal with numbers which contain an extra digit, known as the parity digit. 1970N. R. Scott Electronic Computer Technol. v. 217 The correct parity digit is attached to the digit group at the source, and then the augmented group is tested upon reception to determine whether the parity digit and the message digits are still in agreement.
1907Daily Chron. 3 Oct. 2/1 Opening under the parity level prices continued to lose ground every hour up to the close. 1659W. Brough Schism 549 Have all doors shut upon you for your parity-preaching. 1909Westm. Gaz. 20 May 12/4 The parity price of Amalgamated was 85 3–16. 1937McIntosh & Orr Pract. Agric. for High Schools 15 Show the actual and parity prices of the major farm products. 1955Times 24 Aug. 7/2 American farm prices are kept relatively high and often above world prices by the arrangements whereby the Government must buy certain produce for stock when its price falls to certain specified percentages of so-called ‘parity prices’.
Sense 7 in Dict. becomes 8. Add: 7. Computing. ellipt. for parity bit, sense 8 below.
1966Communications Assoc. Computing Machinery IX. 695/2 The overriding consideration affecting the choice of character structure is compatibility with serial-by-bit data communication in order to minimize confusion. An eight bit character structure (7 ASCII bits and parity) satisfies this requirement. 1981Your Computer (Austral.) May–June 100/1 Parity, an extra bit on the end of a character or byte for error detection.
▪ II. parity2 Obstetr. Med.|ˈpærɪtɪ|
[f. par-ous a. + -ity.]
The condition of being parous; the fact of having borne children.
1878Sir J. Williams in Obstet. Trans. (1879) XX. 173 Diagnosis of Parity. Ibid., Circumstances..in which proof of parity or nulliparity may turn out to be proof of innocence or guilt. 1889J. M. Duncan Clin. Lect. Dis. Women (ed. 4) Index 535 Signs of Parity. 1898G. E. Herman Dis. Women ix. 87.
Add:2. The number of times a particular woman has previously conceived (or occas. given birth).
1921Jrnl. Obstetr. & Gynæcol. XXVIII. 69 The average parity of the multiparæ was 5.7 pregnancies. 1933J. M. M. Kerr Maternal Mortality & Morbidity i. 20 The mortalities in mothers of varying parity are presented below, the death-rates being expressed as a percentage of the average rate in all births irrespective of parity. 1964Obstetr. & Gynecol. XXIII. 165/1 The anticipated increase in higher parities was seen in the multiparas, significant numbers of patients with 3 or more prior viable pregnancies being seen. 1987Brit. Med. Jrnl. 8 Aug. 355/1, 64 Women..were compared with 128 controls individually matched for age, parity, hospital of delivery, and year of delivery. |