Father finds shelter obvious (6)
I believe the answer is:
patent
'obvious' is the definition.
(similar in meaning)
'father finds shelter' is the wordplay.
'father' becomes 'pa' (pa can mean dad or father).
'finds' means one lot of letters go next to another.
'shelter' becomes 'tent' (canvas shelter).
'pa'+'tent'='PATENT'
(Other definitions for patent that I've seen before include "Document granting an inventor sole rights to an invention" , "Sole right to exploit an invention" , "Obvious - property right to invention" , "Registration of ownership of invention" , "Manifest" .)