Sign of love, chaps? (4)
I believe the answer is:
omen
'sign' is the definition.
(I know that omen is a type of sign)
'love chaps?' is the wordplay.
'love' becomes 'o' (love means zero in tennis).
'chaps?' becomes 'men' (chap means a man).
'o'+'men'='OMEN'
'of' acts as a link.
(Other definitions for omen that I've seen before include "Forewarning, harbinger" , "writing on the wall" , "Portent, prophetic sign" , "Straw in the wind" , "Sign of a future event, good or bad" .)