Tipping hat, single man is assiduous (8)
I believe the answer is:
diligent
'assiduous' is the definition.
(similar in meaning)
'tipping hat single man' is the wordplay.
'tipping' shows that the letters should be reversed in order.
'hat' becomes 'lid' (synonyms).
'single' becomes 'i' (one).
'man' becomes 'gent' (gent is a kind of man).
'lid' back-to-front is 'dil'.
'dil'+'i'+'gent'='DILIGENT'
'is' acts as a link.
(Other definitions for diligent that I've seen before include "Taking trouble" , "Painstaking - I tingled (anag)" , "Conscientious and careful" , "Steady in application and industry" , "Assiduous" .)