Tough outlaw left, facing hesitation (7)
I believe the answer is:
hoodlum
'tough' is the definition.
(I know that tough can be written as hoodlum)
'outlaw left facing hesitation' is the wordplay.
'outlaw' becomes 'hood' (hood is a kind of outlaw).
'left' becomes 'l' (common abbreviation).
'facing' says to put letters next to each other.
'hesitation' becomes 'um' (um is said in hesitation).
'hood'+'l'+'um'='HOODLUM'
(Other definitions for hoodlum that I've seen before include "Young thug or gangster" , "Small-time criminal" , "One breaks the law" , "Punk" , "Hooligan" .)