Ingest (3)
I believe the answer is:
eat
'ingest' is the definition.
(eating is a kind of ingesting)
This is the entire clue.
(Other definitions for eat that I've seen before include "Do cats - bats? Do bats - cats? (Alice in Wonderland)" , "put away" , "Gobble up" , "Partake of" , "Dine in a restaurant" .)