Socially, oddly withdrawn and unctuous (4)
I believe the answer is:
oily
'unctuous' is the definition.
(I've seen this before)
'socially oddly withdrawn' is the wordplay.
'oddly withdrawn' means one should take alternating letters (letters in odd-numbered positions removed).
The alternate letters of 'socially' are 'OILY'.
'and' is the link.
(Other definitions for oily that I've seen before include "Smarmy" , "covered in grease" , "Greasy - obsequious" , "Viscous" , "Covered in lubricant" .)