Hearing of a nobleman giving you time of day? (5)
I believe the answer is:
night
'time of day?' is the definition.
(night is a kind of time of day)
'hearing of a nobleman' is the wordplay.
'hearing of' shows a homophone (sound like).
'a nobleman' becomes 'knight' (I've seen this before).
'knight' sounds like 'NIGHT'.
'giving you' acts as a link.
(Other definitions for night that I've seen before include "period of gloom" , "A Hard Day's (the Beatles)" , "Evening" , "Time for turning" , "''Tender is the ...'' (F Scott Fitzgerald)|" .)