Officer is in charge of venomous types (11)
I believe the answer is:
copperheads
'venomous types' is the definition.
Although both the answer and definition are plural nouns, I don't see how they can define each other.
'officer is in charge of' is the wordplay.
'officer' becomes 'copper' (copper is a kind of officer).
'is in charge of' becomes 'heads' (I've seen this in another clue).
'copper'+'heads'='COPPERHEADS'
Can you help me to learn more?
(Other definitions for copperheads that I've seen before include "ophidians?" , "snakes" .)