Dribble leftovers on road heading west (5)

I believe the answer is:

drool

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'dribble' is the definition.
(synonyms)

'leftovers on road heading west' is the wordplay.
'leftovers on' becomes 'loo' (I can't justify this - if you can you should believe this answer much more).
'road' becomes 'rd' (abbreviation).
'heading west' says the letters should be written backwards.
'loo'+'rd'='loord'
'loord' reversed gives 'DROOL'.

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(Other definitions for drool that I've seen before include "dribble" , "Show excitement" , "Let saliva run from the mouth" , "Slaver - drivel" , "Salivate" .)

I've seen this clue in The Independent.

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