New coat: yes, it's warmer (3,4)
I believe the answer is:
tea cosy
'warmer' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'new coat yes' is the wordplay.
'new' indicates an anagram.
'coat'+'yes'='coatyes'
'coatyes' anagrammed gives 'TEA-COSY'.
'it's' is the link.
Can you help me to learn more?
(Other definitions for tea cosy that I've seen before include "It keeps the beverage hot" , "put on for warmth" , "leaves in a hot state in this?" , "Knitted item" , "Pot cover" .)