Mum with cold needs rainwear (3)
I believe the answer is:
mac
'rainwear' is the definition.
Both the answer and definition are singular nouns.
Maybe they are linked in a way I don't understand?
'mum with cold' is the wordplay.
'mum' becomes 'ma' (ma can mean mother).
'with' means one lot of letters go next to another.
'cold' becomes 'c' (eg on taps).
'ma'+'c'='MAC'
'needs' acts as a link.
Can you help me to learn more?
(Other definitions for mac that I've seen before include "Waterproof raincoat, in short" , "A rainproof" , "one used in shower?" , "It may help you keep dry" , "laptop?" .)