adult in WordNet English dictionary

1. any mature animal
   adult 
   
2. a fully developed person from maturity onward
   adult  grownup 
   

1. (of animals) fully developed
   "an adult animal"; "a grown woman"
   adult  big  full-grown  fully grown  grown  grownup 
   
2. designed to arouse lust
   "pornographic films and magazines"; "adult movies"
   pornographic  adult