To talk of robes (5)
I believe the answer is:
togas
'robes' is the definition.
(I've seen this in another clue)
'to talk' is the wordplay.
'talk' becomes 'gas' (I've seen this before).
'to'+'gas'='TOGAS'
'of' acts as a link.
(Other definitions for togas that I've seen before include "garments worn by ancient Romans" , "What some ancient citizens wore" , "Roman garments" , "clothing" .)