Headless chickens are following new trap (7)
I believe the answer is:
ensnare
'trap' is the definition.
(I know that trap can be written as ensnare)
'headless chickens are following new' is the wordplay.
'headless' means to remove the first letter.
'chickens' becomes 'hens' (hen is a kind of chicken).
'following' means one lot of letters go next to another.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'hens' with its initial letter removed is 'ens'.
'are' put after 'n' is 'nare'.
'ens'+'nare'='ENSNARE'
(Other definitions for ensnare that I've seen before include "Ecstatic expression of feeling" , "Catch as if in a trap or net" , "Capture, trap" , "Ambush" .)