501 on edge part company (7)

I believe the answer is:

diverge

'part company' is the definition.
(thesaurus)

'501 on edge' is the wordplay.
'e0v' becomes 'di'.
'on' says to put letters next to each other.
'edge' becomes 'verge' (verge is a kind of edge).
'di'+'verge'='DIVERGE'

(Other definitions for diverge that I've seen before include "lead in different directions" , "stray from course" , "Move away from" , "Go different ways" , "conflict" .)

I've seen this clue in The Irish Independent.

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