Crossword Genius

Waterproof coat found by a mother – something on road? (7)

Ross

I believe the answer is:

macadam

I'm a little stuck... Click here to teach me more about this clue!

'something on road?' is the definition.
I can't tell whether this defines the answer.

'waterproof coat found by a mother' is the wordplay.
'waterproof coat' becomes 'mac' (I've seen this before).
'found by' says to put letters next to each other.
'mother' becomes 'dam' (female parent of an animal).
'mac'+'a'+'dam'='MACADAM'

Can you help me to learn more?

(Other definitions for macadam that I've seen before include "Paving material" , "(Inventor of) road surface" , "Tarmac" , "Road surfacing material" , "Road surface made of broken stone and tar" .)

I've seen this clue in The Guardian.
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