One's bowled over by girl presented with large teapots and hair extensions (9)
I believe the answer is:
sideburns
'hair extensions' is the definition.
Although both the answer and definition are plural nouns, I cannot understand how one could define the other.
'one's bowled over by girl presented with large teapots' is the wordplay.
'one's' becomes 'i's' (Roman numeral).
'bowled over' says the letters should be written in reverse.
'by' is a charade indicator (letters next to each other).
'girl presented' becomes 'deb' (debutante, girl presented to fashionable society).
'with large teapots' becomes 'urns' (I can't explain this - if you can you should give a lot more credence to this answer).
'is' in reverse letter order is 'si'.
'si'+'deb'+'urns'='SIDEBURNS'
'and' is the link.
Can you help me to learn more?
(Other definitions for sideburns that I've seen before include "hirsute growth" , "Cheeky display" , "Facial whiskers" , "Hair" , "temple adornments" .)