consonant sound in some English words derived from Greek. The p- typically is silent in English but pronounced in French, German, Spanish, etc.
It is to be desired that it were sounded in English, also, at least in scientific and learned words; since the reduction of pneo- to neo-, pneu- to new-, and pnyx to nix, is a loss to etymology and intelligibility, and a weakening of the resources of the language. [OED]
In Latin assimilated to following -c-, -f-, -g-, -p-, and often -r- and -m-. In Old French the prefix appears in the full Latin form only "in learned adoptions of old Latin compounds" [OED], and in popular use it was represented by sous-, sou-; as in French souvenir from Latin subvenire, souscrire (Old French souzescrire) from subscribere, etc.
The original meaning is now obscured in many words from Latin (suggest, suspect, subject, etc.). The prefix is active in Modern English, sometimes meaning "subordinate" (as in subcontractor); "inferior" (17c., as in subhuman); "smaller" (18c.); "a part or division of" (c. 1800, as in subcontinent).
word-forming element meaning "man, male, masculine," from Greek andro-, combining form of anēr (genitive andros) "a man, a male" (as opposed to a woman, a youth, or a god), from PIE root *ner- (2) "man," also "vigorous, vital, strong."
Equivalent to Latin vir (see virile). Sometimes in later use equivalent to anthrōpos, Latin homo "a person, a human being," and in compounds it often retain this genderless sense (e.g. androcephalous "having a human head," said of monsters including the Sphinx, which in Greece was female).