Powerful petty officer gets mobile home (6)
I believe the answer is:
potent
'powerful' is the definition.
(I know that powerful can be written as potent)
'petty officer gets mobile home' is the wordplay.
'petty officer' becomes 'po' (naval abbreviation).
'gets' is a charade indicator (letters next to each other).
'mobile home' becomes 'tent' (I've seen this in another clue).
'po'+'tent'='POTENT'
(Other definitions for potent that I've seen before include "Powerful or effective" , "Maybe overpowering" , "Strong or concentrated, like some drink" , "Top Ten (anag.)" , "Powerful, influential" .)