Adult

1. n. A person, animal, or plant grown to full size and strength; one who has reached maturity.
2. a. Having arrived at maturity, or to full size and strength; matured; as, an adult person or plant; an adult ape; an adult age.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.