Dad takes shelter, that's obvious (6)
I believe the answer is:
patent
'obvious' is the definition.
(similar in meaning)
'dad takes shelter' is the wordplay.
'dad' becomes 'pa' (both can mean one's father).
'takes' says to put letters next to each other.
'shelter' becomes 'tent' (canvas shelter).
'pa'+'tent'='PATENT'
'that's' acts as a link.
(Other definitions for patent that I've seen before include "Flagrant" , "Licence for inventors; obvious" , "Copyright" , "It protects an invention" , "Open the right to an invention" .)