Like a family (4)
I believe the answer is:
akin
'like' is the definition.
(I've seen this before)
'a family' is the wordplay.
'family' becomes 'kin' (synonyms).
'a'+'kin'='AKIN'
(Other definitions for akin that I've seen before include "Related or similar - as a relative?" , "Having similar characteristics" , "Related by blood" , "Related or similiar" , "Similar, like" .)