daguerreotype n.

late 15c., "symbol, emblem," from Latin typus "figure, image, form, kind," from Greek typos "a blow, dent, impression, mark, effect of a blow; figure in relief, image, statue; anything wrought of metal or stone; general form, character; outline, sketch," from root of typtein "to strike, beat," from PIE *tup-, variant of root *(s)teu- (1) "to push, stick, knock, beat" (see steep (adj.)).

Extended 1713 to printing blocks of metal or wood with letters or characters carved on their faces, usually in relief, adapted for use in letterpress printing. The meaning "general form or character of some kind, class" is attested in English by 1843, though the corresponding words had that sense in Latin and Greek. To be (someone's) type "be the sort of person that person is attracted to" is recorded from 1934.

type of photograph on glass with lights given by silver and shades by a dark background showing through, 1855, American English, apparently from Greek ambrotos "immortal, imperishable" (see ambrosia), with second element from daguerreotype.

This invention consists in an improved process of taking photographic pictures upon glass, and also of beautifying and preserving the same, which process I have styled "ambrotype." My improved process has reference to the art of taking pictures photographically on a film of collodion upon the surface of a sheet of glass, the collodion being suitably prepared for the purpose. By the use of the said process, the beauty and permanency of such pictures are greatly increased, and I have on this account styled the process "ambrotype," from the Greek word ambrotos, immortal. ["Specification of the Patent granted to James A. Cutting, of Boston, in the United States of America, Photographer, for an Improved Process of taking Photographic Pictures upon Glass and also of Beautifying and Preserving the same. Dated London, July 26, 1854," printed in Journal of the Franklin Institute, September 1855]

"photograph picture obtained by the use of cyanide," 1842, from cyan- + ending from daguerreotype (see type (n.)).