premature Definition

premature
adj

1. medicine.
Said of human birth: occurring less than 37 weeks after conception.
Thesaurus: early, preterm, preemie (US slang), embryonic.
2. Occurring before the usual or expected time.

Example: premature senility
Thesaurus: immature, early, undeveloped, incomplete, embryonic, half-formed, raw, unripe, green, precocious, forward, unseasonable, inopportune; Antonym: late, tardy.
3. Said of a decision, etc: over-hasty; impulsive.

Derivative: prematurely
adverb

Etymology: 16c: from Latin praematurus, from prae before + maturus ripe.