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aˈblate, v.
[f. L. ablāt- ppl. stem of aufer-re to carry away; f. ab off, away + fer-re, pa. pple. lāt-um, to bear.]
a. To take away, remove. In mod. use spec. by ablation. Obs. in general sense; in modern use as back-formation from ablation.
1542Boorde Dyetary (1870) xxi. 284 Althoughe the skynnes or huskes be ablated, or cast away. 1606Warner Albion's Eng. xv. xcv. 379 A conquest though it much addes, alters, and ablates. 1902Encycl. Brit. XXXI. 744 When the cerebral hemispheres have been ablated. 1923Times Lit. Suppl. 16 Aug. 541/1 The low sun..evaporates or ‘ablates’ the ice continually. 1974Nature 8 Nov. 94/1 Rockets can only pick up the micrometeoroids after they have been retarded by the atmosphere and contaminated by meteoric dust ablated from larger meteoroids.
b. Astr. and Astronautics. trans. To erode by ablation.
1952Astrophysical Jrnl. CXVI. 203 In the meteor work..only the parameter (where Γ is the retardation coefficient and ζ the energy to ablate unit mass of meteor material)..could be determined from the observations. 1959Dublin Evening Press 8 June 5/6 The nose cone is covered with several layers of tough plastic highly resistant to temperature. As the cone falls back through the atmosphere, the layers of plastic are eroded, or ‘ablated’, off in turn, but they achieve their ultimate object of protecting the cone's main substance. 1978Sci. Amer. Mar. 84/2 Even though the atmosphere of Mars is thin, it is dense enough to ablate and break up small incoming meteoroids before they reach the surface.
c. intr. To undergo ablation; to lose mass as a result of heating produced by friction.
1960Jrnl. Aero/Space Sci. XXVII. 539/1 The total radiation..was measured as the model ablated in the arc tunnel. 1963Jrnl. Geophysical Res. LXVIII. 4329/1 At sufficiently low pressures, tektite glass ablates without producing any ring waves. 1974Nature 26 Apr. 811/2 Some australites starting quite spherical ablate to characteristic button-like shapes.
Hence aˈblating vbl. n. and ppl. a.; aˈblated ppl. a.
1959W. A. Heflin Aerospace Gloss. 1/1 For hypersonic reentry bodies, ablating materials must handle temperatures in surrounding air up to 15,000° F. Ibid., Ablating nose cone, a nose cone designed to prevent heat transfer to its internal structure by the use of an ablating material. 1961J. F. Vedder in F. S. Johnson Satellite Environment Handbk. v. 97 Most meteoritic material, by the time it reaches the Earth's surface, has been reduced to dust or to spherules of ablated material in its passage through the atmosphere. 1980Nature 1 May 12/2 Excited atoms and molecules emit radiation and the luminous power so produced has been found to be proportional to the rate of loss of kinetic energy of the ablated atoms. |