Bloomer I committed originally in city of star-crossed lovers (8)
I believe the answer is:
veronica
'bloomer' is the definition.
(veronica is a kind of flowering plant)
'i committed originally in city of star-crossed lovers' is the wordplay.
'originally' says to take the initial letters.
'in' means one lot of letters goes inside another.
'city of star-crossed lovers' becomes 'verona' (setting of Romeo and Juliet).
The initial letter of 'committed' is 'c'.
'i'+'c'='ic'
'ic' placed into 'verona' is 'VERONICA'.
(Other definitions for veronica that I've seen before include "Lady" , "Saint who wiped Christ's face on the Via Dolorosa" , "Girl" , "Plant also called speedwell -- I've no car (anag)" , "Plant with spikes of blue or purple" .)