Time flew backwards, the endless bit (7)
I believe the answer is:
twelfth
'bit' is the definition.
Both the definition and answer are adjectives. Maybe they are linked in a way I don't understand?
'time flew backwards the endless' is the wordplay.
'time' becomes 't' (abbreviation).
'backwards' says the letters should be written backwards.
'endless' means to remove the last letter.
'flew' back-to-front is 'welf'.
'the' with its final letter taken off is 'th'.
't'+'welf'+'th'='TWELFTH'
Can you help me to learn more?
(Other definitions for twelfth that I've seen before include "Play by 8" , "The evening of 5 January" , "One, of a dozen" , "Last of a dozen" , "The Glorious -- is when grouse-shooting begins" .)