Folded coat containing earth and bit of dirt (7)
I believe the answer is:
pleated
'folded' is the definition.
(pleating is a kind of folding)
'coat containing earth and bit of dirt' is the wordplay.
'coat' becomes 'plate' (plating is a kind of coating**).
'containing' is an insertion indicator.
'earth' becomes 'e'.
'and' is a charade indicator (letters next to each other).
'bit of' says to take the initial letters.
The initial letter of 'dirt' is 'd'.
'plate' going around 'e' is 'pleate'.
'pleate'+'d'='PLEATED'
(Other definitions for pleated that I've seen before include "With folds sewn in" , "Folded and stitched" , "Given creases" , "(Garment) with folds" , "Folded and sewn" .)