/ Dictionary / Index I infancy: Meaning and Definition of Find definitions for: in•fan•cy Pronunciation: (in'fun-sē), [key] — pl. -cies. the state or period of being an infant; very early childhood, usually the period before being able to walk; babyhood. the corresponding period in the existence of anything; very early stage: Space science is in its infancy. infants collectively. the period of life to the age of majority, 21 years at common law but now usually 18; minority; nonage. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: infancy (Thesaurus) infamy infant Related Content Daily Word Quiz: sequester Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language