Peculiar for Miriam not to be on time but it doesn't matter (10)
I believe the answer is:
immaterial
'peculiar' is the definition.
Both the answer and definition are adjectives. Maybe you can see a link between them that I don't see?
'miriam not to be on time but it doesn't matter' is the wordplay.
I cannot really understand how this works, but
'on' could be 'at' (I've seen this in other clues) and 'at' is found within the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is found in the answer.
an anagram of 'miriam' is 'immria' which is located in the left over letters.
A single letter 'l' remains which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'for' acts as a link.
Can you help me to learn more?
(Other definitions for immaterial that I've seen before include "of no importance" , "Irrelevant" , "unimportant" .)