Some logjam, bore, ending — there’s celebration! (8)
I believe the answer is:
jamboree
'celebration' is the definition.
(jamboree is a kind of celebration)
'some logjam bore ending' is the wordplay.
'some' indicates the answer is hidden within the clue (some of the parts of the word are used).
'JAMBOREE' can be found hidden inside 'logjam bore ending'.
'there's' acts as a link.
(Other definitions for jamboree that I've seen before include "beano" , "Large scout rally" , "Spree" , "Scout gathering; big party" , "Party - gathering of Scouts" .)