Cilla bursts into flower (5)
I believe the answer is:
lilac
'flower' is the definition.
(thesaurus)
'cilla bursts' is the wordplay.
'bursts' indicates an anagram.
'cilla' anagrammed gives 'LILAC'.
'into' acts as a link.
(Other definitions for lilac that I've seen before include "Genus Syringa shrub" , "Tree with pink blossoms" , "Shrub with fragment purple or white flowers" , "garden ornamental" , "Fragrant shrub; colour" .)