Party in British wood (4)
I believe the answer is:
bash
'party' is the definition.
(term for a party or celebration)
'british wood' is the wordplay.
'british' becomes 'b' (abbreviation e.g. in BBC).
'wood' becomes 'ash' (wood from an ash tree).
'b'+'ash'='BASH'
'in' acts as a link.
(Other definitions for bash that I've seen before include "Shindig, function" , "Smite; a party" , "Party; attempt (slang)" , "knock" , "Party - whack" .)