Dip partly responsible for swimmer's ear? (7)
I believe the answer is:
immerse
'dip' is the definition.
(thesaurus)
'partly responsible for swimmer's ear?' is the wordplay.
'partly responsible for' indicates a hidden word.
'IMMERSE' can be found hidden inside 'swimmers ear'.
(Other definitions for immerse that I've seen before include "Submerge in water as once for baptism" , "Cover with water, dip into" , "Dip totally into liquid" , "Dunk" , "dive" .)