Endless ingrained dirt, ghastly (4)

I believe the answer is:

grim

'ghastly' is the definition.
(I've seen this before)

'endless ingrained dirt' is the wordplay.
'endless' means to remove the last letter.
'ingrained dirt' becomes 'grime' (I've seen this before).
'grime' with its final letter taken off is 'GRIM'.

(Other definitions for grim that I've seen before include "Unrelentingly harsh" , "Stern and unsmiling" , "Frightful" , "Harsh and merciless" , "Dreadful" .)

I've seen this clue in The Telegraph.

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