Allow to (3)
I believe the answer is:
let
'allow to' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for let that I've seen before include "Was inclined to ignore" , "Allow on the tennis court" , "Reason for scrubbing service" , "& 15 Triple (anag.)" , "Allow or rent" .)