suppressor
(səˈprɛsə(r))
Also 6–7 -our; see also suppresser.
[f. suppress + -or. Late L. had suppressor.]
1. a. One who or that which suppresses.
| 1560 in Maitl. Club Misc. III. 217 The Pape quhai is the verray Antichriste and suppressour of Godis glorie. 1632 Lithgow Trav. ix. 388 He was no suppressour of the subiects. 1682 Sir T. Browne Chr. Mor. 13 Humility and charity, the great suppressors of envy. 1711 E. Ward Vulgus Brit. viii. 91 And so from a Rude Mob became, The fierce Suppressors of the same. 1868 Freeman Norm. Conq. II. viii. 194 Rudolf of Ivry..the savage suppressor of the great peasant revolt. |
b. spec. A device for stopping a machine or part to which it is fitted from causing electrical interference.
| 1930 Engineering 14 Nov. 626/1 A diagram..is given in Fig. 16, the transmitting and receiving suppressors being marked TS1 and TS2. 1948 Electronic Engin. XX. 95 An ignition suppressor for fitting in the H.T. supply lead from the coil. 1955 [see suppress v. 8 b]. 1970 [see suppressed ppl. a. d]. |
2. Genetics. A gene in whose presence the effects of some other gene are not expressed. Also
suppressor gene.
| 1928 Zeitschr. f. Induktive Abstammungs- und Vererbungslehre XLVI. 85 (heading) The genetics of ‘black suppressor’ in Drosophila melanogaster. 1932 Amer. Naturalist LXVI. 323 That the suppressor is a translocated wild-type allelomorph rather than a mutation in another gene has been proved in certain cases. 1960 Heredity XV. 91 The phenotypic manifestation of the suppressor gene is hidden by the mutation en. 1966 Ann. Rev. Microbiol. XX. 409 The best characterized and most intensively studied of the suppressor mutations which affect the translation process are the suppressors of the two classes of mutants, ‘amber’ and ‘ochre’. |
3. Electronics.
= suppressor grid, sense 4 below.
| 1937 F. E. Terman Radio Engin. (ed. 2) iv. 128 The virtual cathode in conjunction with the plate and suppressor grid forms the equivalent of a triode tube in which the suppressor is the grid. 1959 [see grid 5 a]. 1968 Romanowitz & Puckett Introd. Electronics vi. 237 The suppressor is usually connected to the cathode and is thus at full negative potential with respect to the plate. |
4. Special
Combs.:
suppressor (T) cell Immunol., a thymus-dependent lymphocyte which can suppress the stimulation of antibody production in lymphocytes in the presence of antigen;
suppressor grid Electronics, in a thermionic valve, a coarse grid situated between electrodes (
usu. the screen grid and the anode) so as to stop secondary electrons emitted by the latter from reaching the former.
| 1972 Jrnl. Immunol. CVIII. 590/1 It is possible that there are separate populations of activator (x) and suppressor (y) T cells. 1979 Jrnl. Exper. Med. CXLIX. 1018 The suppressor T Cells regualted the DH [sc. delayed hypersensitivity] in the induction stage. 1981 Nature 23 July 357/2 Nonspecific suppressor cells may be one explanation for the severe immunodeficiency and the recurrent infectious complications characteristic of patients with chronic GvHD [sc. graft-versus-host disease]. |
| 1931 Electronics Nov. 176/2 In order to avoid the effects of secondary emission from the plate..an auxiliary electrode was inserted to suppress this secondary current. The advantages of this same sort of suppressor grid are utilized in the..power pentode design. 1944 Electronic Engin. XVII. 163 The suppressor grids are generally operated at cathode potential. 1974 Harvey & Bohlmann Stereo F.M. Radio Handbk. ii. 13 If a modulating signal is now applied, the bias on the suppressor grid is alternately raised and lowered in sympathy with the modulating signal. |