Second thoughts about material with spots (6)
I believe the answer is:
'spots' is the definition.
(I know this)
'second thoughts about material' is the wordplay.
'second thoughts' becomes 'ps' (as in a PS in a letter).
'about' is an insertion indicator.
'material' becomes 'lace' (lace is a kind of material).
'ps' going around 'lace' is 'PLACES'.
'with' acts as a link.
(Other definitions for places that I've seen before include "Locations" , "Sites" .)