Delayed because of wet, we hear (7)
I believe the answer is:
overdue
'delayed' is the definition.
(something overdue has been delayed)
'because of wet we hear' is the wordplay.
'because of' becomes 'over' (eg 'he's upset over it').
'wet' becomes 'dew' (moisture on the ground).
'we hear' indicates a 'sounds like' (homophone) clue.
'dew' is a homophone of 'due'.
'over'+'due'='OVERDUE'
(Other definitions for overdue that I've seen before include "Delayed" , "Opposite of 1 ac." , "Later than the appointed time, as for bill payment" , "In arrears" , "Past the expected time of arrival" .)