Sheepish individual, about six (5)
I believe the answer is:
ovine
'sheepish' is the definition.
(thesaurus)
'individual about six' is the wordplay.
'individual' becomes 'one'.
'about' means one lot of letters goes inside another.
'six' becomes 'vi' ('vi' can be a synonym of 'six').
'one' going around 'vi' is 'OVINE'.
(Other definitions for ovine that I've seen before include "like a mug" , "Sheep-like" , "Like the Cheviots" , "Resembling a sheep" , "Like a sheep" .)