Chaperone, often (5)
I believe the answer is:
adult
'chaperone often' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for adult that I've seen before include "Mature, fully grown" , "one no longer in minority" , "I wasn't born yesterday" , "Mature, fully-grown" , "(Of an animal) fully developed" .)