- proto-
- proto- [prōt′ō, prōt′ə][Gr prōto- < prōtos, first < IE * pṛto- < base * pro-, early, ahead > L pro-, Gr pro-] combining form1. first in time, original, primitive [protoplast]2. first in importance, principal, chief [protonotary]3. [P-] prehistoric or original: said of a people or language [Proto-Germanic]4.a) forming nouns on the way to becoming the (specified) thing or kind of person [proto-suburbia, a proto-terrorist]b) forming adjectives on the way to having the (specified) quality or relationship [a proto-Cubist painting]5. Chem.a) being that member of a series of compounds having the lowest proportion of the (specified) element or radical [protoxide]b) being the parent form of a (specified) substance
English World dictionary. V. Neufeldt. 2014.