Flower got bigger (4)
I believe the answer is:
rose
'flower' is the definition.
(I know that rose is a flower)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for rose that I've seen before include "vacated bed" , "Fragrant flower" , "Flower - girl - got up" , "grew" , "Floral emblem of England" .)