sporadicadj.

1813 T. Young in Q. Rev. Oct. 255 All the Asiatic and European languages..which may be subdivided into five orders, Sporadic, Caucasian, Tartarian, Siberian, and Insular.

1830 J. Lindley Introd. Nat. Syst. Bot. 90 About 92 genera..are what are called sporadic, or dispersed over different and widely separated regions.

1856 S. P. Woodward Man. Mollusca iii. 350 Those species which characterise particular regions are termed ‘endemic’... The others, sometimes called ‘sporadic’, possess great facilities for diffusion.

1865 F. W. Farrar Chapters on Lang. 29 In various sporadic families, which some would call Turanian.

1878 M. Foster Text Bk. Physiol. (ed. 2) i. iii. 89 In the sporadic ganglia the evidence of automatic action seems more clear.

1861 H. Bushnell Christian Nurture i. viii. 196 Sporadic cases of sanctification.

1864 R. F. Burton Mission to Gelele II. 71 Sporadic heroines..are found in every clime and in all ages.

1877 S. J. Owen in Marquess Wellesley Select. Despatches Introd. p. xix A series of sporadic encounters of a petty and inglorious..character.

1882 Times 7 Feb. The continuance of sporadic troubles in Basutoland.

1821 S. Smith Wks. (1850) 316 Has any sporadic squire the right to say, that it shall be punished with death?

1875 H. James Roderick Hudson iv. 129 Rowland began to think of the Baden episode as a mere sporadic piece of disorder.

1878 B. Stewart & P. G. Tait Unseen Universe vii. §217. 215 This production was..a sporadic or abrupt act.

1929 C. Hoffmeister in Astrophysical Jrnl. 69 167 I have developed some methods..to find out..which portion of meteors..may be regarded as ‘sporadic’, i.e., the directions of motions being distributed in an irregular way without indication of radiation in currents... Meteors emanating from a real radiant are mostly of cometary character and sporadic meteors are mostly of interstellar origin.

1954 A. C. B. Lovell Meteor Astron. xxi. 429 A good deal of attention has been given..to the problem of the velocity of sporadic meteors, and the conclusion now seems inescapable that they must be contained in the solar system as distinct from the interstellar view which has prevailed for so long.

1961 D. W. R. McKinley Meteor Sci. & Engin. i. 3 The number of sporadics greatly outweighs the total number of meteors belonging to the well-known showers.

1978 V. F. Buchwald Iron Meteorites I. i. 11/1 It is commonly inferred that all meteors—including the sporadic—are fragments of comets.

1842 Penny Cycl. XXII. 378/1 The occasional occurrence of diseases..usually epidemic, in a sporadic form.

1852 H. Rogers Eclipse of Faith 146 Its manifestation may be sporadic, but it will be in one race as in another.

1865 T. Carlyle Hist. Friedrich II of Prussia V. xviii. xiv. 368 Meanwhile, the Austrians on front do, in a sporadic way, attack..our batteries.

1881 B. F. Westcott & F. J. A. Hort New Test. in Orig. Greek II. Introd. iii. 81 All known MSS shew..traces of sporadic and casual mixture.

1937 Terrestrial Magnetism XLII. 76 No relation between the sporadic E-region ionizations and magnetic disturbances of widespread character is apparent so far.

1949 Nature 2 Apr. 528/2 The usual measure of sporadic E-layer ionization is the so-called ‘critical frequency’, that is, the highest reflected frequency for this layer.

1955 Sci. Amer. Sept. 129/1 One of the outstanding mysteries of the ionosphere is a type of irregularity called ‘sporadic E’.

1967 Economist 22 July 280/1 UHF is virtually immune to sporadic-E problems which so beset VHF.

1974 E. Harnischmacher in F. Verniani Struct. & Dynamics of Upper Atmosphere 272 The Sporadic E layer, Es, is the most irregular and the thinnest layer of the ionosphere.