Boa ... (11)
(Other definitions for constrictor that I've seen before include "One drawing together" , "snake" .)
'boa' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for snake that I've seen before include "Carnivorous reptile" , "Part of plant or hair" , "Wind" , "Move sinuously" , "former EC currency band" .)