Standard loom attached to knitted fabric, briefly (9)
I believe the answer is:
tricolour
'standard' is the definition.
'loom attached to knitted fabric briefly' is the wordplay.
'loom' becomes 'lour'.
'attached to' is a charade indicator (letters next to each other).
'knitted fabric' becomes 'tricot'.
'briefly' means to remove the last letter.
'tricot' with its last letter removed is 'trico'.
'lour' after 'trico' is 'TRICOLOUR'.
(Other definitions for tricolour that I've seen before include "Standard of French perhaps" , "French national flag" , "Having or involving three colours" .)