Exhausted author lying in street (5)
I believe the answer is:
spent
'exhausted' is the definition.
(similar in meaning)
'author lying in street' is the wordplay.
'author' becomes 'pen' (to pen something is to author it).
'lying in' indicates putting letters inside.
'street' becomes 'st' (abbreviation).
'pen' placed into 'st' is 'SPENT'.
(Other definitions for spent that I've seen before include "(Of resources) exhausted" , "Expended" , "Completely exhausted" , "Burned-out" , "Used up; exhausted" .)