mid-15c., "ripe;" 1520s, "existing or done before the proper or usual time, arriving too early at maturity," from Latin praematurus "early ripe" (as fruit), "too early, untimely," from prae "before" (see pre-) + maturus "ripe, timely" (see mature (v.)). Related: Prematurely; prematurity; prematuration.
Premature ejaculation is attested from 1848; the Latin euphemism ejaculatio praecox dates to 1891 in English but was used earlier in German and appears to have been, at first at least, the psychologist's term for it.
adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy).
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Definitions of preemie from WordNet
an infant that is born prior to 37 weeks of gestation;