Legion to become more insignificant? (9)
I believe the answer is:
countless
'legion' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for countless that I've seen before include "Untold" , "Innumerable" , "Legion seeming to be" , "Infinite" , "not so important" .)