Loafer was on line after time (7)
I believe the answer is:
wastrel
'loafer' is the definition.
(thesaurus)
'was on line after time' is the wordplay.
'on' becomes 're' ('on' can be mean 'with reference to').
'line' becomes 'l' (used when specifying particular lines from a poem).
'after' is a charade indicator (letters next to each other).
'time' becomes 't' (abbreviation).
're'+'l'='rel'
'rel' after 't' is 'trel'.
'was'+'trel'='WASTREL'
(Other definitions for wastrel that I've seen before include "Ne'er-do-well" , "Person who dissipates resources self-indulgently" , "Useless person" , "A useless, good for nothing fellow" , "Good-for-nothing person" .)