Large African snake (5)
I believe the answer is:
mamba
'large african snake' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for mamba that I've seen before include "Venomous snake; rhymes with dance" , "Venomous Afr. snake" , "Large African snake" , "serpent" , "Snake that might kill" .)