Need ground by minor thoroughfare extended (9)

I believe the answer is:

broadened

'extended' is the definition.
('broaden' can be a synonym of 'extend')

'need ground by minor thoroughfare' is the wordplay.
'ground' is an anagram indicator ('grind' the letters into a new form).
'by' means one lot of letters go next to another.
'minor thoroughfare' becomes 'B road' (B road).
'need' anagrammed gives 'ened'.
'ened' after 'broad' is 'BROADENED'.

(Another definition for broadened that I've seen is " Widened".)

I've seen this clue in The Independent.

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