Tin-opener, small and dainty (4)
I believe the answer is:
twee
'dainty' is the definition.
(synonyms)
'tin-opener small' is the wordplay.
'opener' suggests taking the first letters.
'small' becomes 'wee' (Scottish term for small).
The first letter of 'tin' is 't'.
't'+'wee'='TWEE'
'and' acts as a link.
(Other definitions for twee that I've seen before include "Affectedly dainty or refined" , "Mawkish" , "Overly precious" , "Sickly sweet" , "Attractively quaint" .)