Origin and history of prototype

late 15c., "symbol, emblem, that by which something is symbolized, distinguishing mark or sign," from Latin typus "figure, image, form, kind," from Greek typos "a blow, dent, impression, mark, effect of a blow;" also "figure in relief, image, statue; anything wrought of metal or stone;" and by extension "general form, character; outline, sketch."

This is from the root of typtein "to strike, beat," which is reconstructed to be from a variant of PIE root *(s)teu- (1) "to push, stick, knock, beat," with derivations referring to projecting objects (source also of Latin stupere "be stunned, amazed;" see steep (adj.)).

Type was extended by 1713 to "small, right-angled printing block of metal or wood having for its face a letter or character, usually in high relief, adapted for use in letterpress printing." Hence "printed characters, characters written in imitation of letterpress printing" (1784).

The meaning "particular mode or style that serves as a guide, representative mode or structure" of some kind or class is attested by 1843, though the Latin and Greek words had that notion. In natural history, type as "a species which most perfectly exhibits the essential characteristics of the family or group," is attested by 1837.

Hence the sense of "person of a particular character," (by 1922); to be (someone's) type "be the sort of person that person is attracted to" is recorded by 1934.

"pertaining to a prototype, being or constituting a primary form," 1640s, from prototype + -ical. Alternative prototypal is from 1690s.

before vowels prot-, word-forming element in compounds of Greek origin meaning "first, source, parent, preceding, earliest form, original, basic," from Greek prōto-, from prōtos "first" (from PIE *pre-, from root *per- (1) "forward," hence "before, first"). It is also used in forming words in the sciences and to form compounds having historical reference (such as Proto-Indo-European).