Excited seeing leg, not small, in flimsy robe (8)
I believe the answer is:
negligee
'flimsy robe' is the definition.
'excited seeing leg not small' is the wordplay.
'excited' indicates an anagram.
'not' suggests deleting specific letters.
'small' becomes 's' (abbreviation - e.g. clothes size).
'seeing'+'leg'='seeingleg'
'seeingleg' with 's' removed is 'eeingleg'.
'eeingleg' is an anagram of 'NEGLIGEE'.
'in' is the link.
(Other definitions for negligee that I've seen before include "Loose dressing gown for women" , "Loose flimsy garment" , "Nightie" , "Thin dressing gown" , "Night shift" .)