Drop is put into drink (6)
I believe the answer is:
disown
'drop' is the definition.
Although both the answer and definition are verbs in their base form, I don't see how they can define each other.
'is put into drink' is the wordplay.
'put into' means one lot of letters goes inside another.
'drink' becomes 'down' (to down something can mean to drink it quickly).
'is' put into 'down' is 'DISOWN'.
Can you help me to learn more?
(Other definitions for disown that I've seen before include "Refuse responsibility for" , "Repudiate, cast off" , "Repudiate or refuse to acknowledge a relationship" , "Wins do (anag)" , "Reject all connection with, refuse to acknowledge" .)