Return key with one caught opening drawer (7)
I believe the answer is:
enticer
'drawer' is the definition.
'return key with one caught opening' is the wordplay.
'return key' becomes 'enter'.
'with' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'opening' indicates taking the first letters.
The initial letter of 'caught' is 'c'.
'i'+'c'='ic'
'enter' enclosing 'ic' is 'ENTICER'.
(Other definitions for enticer that I've seen before include "temptress?" , "Who offers temptation" .)