Tricky question: given time to relax, start to reply (6)
I believe the answer is:
teaser
'tricky question' is the definition.
(I've seen this before)
'time to relax start to reply' is the wordplay.
'time' becomes 't'.
'to relax' becomes 'ease' (I've seen this before).
'start to' suggests taking the first letters.
The initial letter of 'reply' is 'r'.
't'+'ease'+'r'='TEASER'
'given' acts as a link.
(Other definitions for teaser that I've seen before include "A difficult problem of Teresa" , "One who annoys people or cards wool" , "Difficult problem concerning Easter" , "One who irritates playfully" , "One who pulls someone's leg" .)