New product for clapping beneath tavern (10)
I believe the answer is:
innovation
'new product' is the definition.
(I've seen this before)
'clapping beneath tavern' is the wordplay.
'clapping' becomes 'ovation' (I've seen this before).
'beneath' says to put letters next to each other (in a down clue, some letters go below others).
'tavern' becomes 'inn' (I've seen this in another clue).
'ovation' after 'inn' is 'INNOVATION'.
'for' is the link.
(Other definitions for innovation that I've seen before include "original" , "Something introduced as a novelty" , "Something new" , "What's new" , "New product" .)