Intricate mosaic, but very tiny (9)

I believe the answer is:

subatomic

'very tiny' is the definition.

'intricate mosaic but' is the wordplay.
'intricate' is an anagram indicator.
'mosaic'+'but'='mosaicbut'
'mosaicbut' with letters rearranged gives 'SUBATOMIC'.

(Other definitions for subatomic that I've seen before include "Like 9 across" , "Smaller than a basic particle of matter" , "Of smaller than elementary particles" .)

I've seen this clue in The Telegraph.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.