Favourite place to study a flower (7)
I believe the answer is:
petunia
'flower' is the definition.
(type of flower)
'favourite place to study a' is the wordplay.
'favourite' becomes 'pet' (synonyms).
'place to study' becomes 'uni' (university).
'pet'+'uni'+'a'='PETUNIA'
(Other definitions for petunia that I've seen before include "Plant related to tobacco" , "Flowering plant" , "Flower - tuna pie (anag)" , "Popular plant for baskets" , "Garden plant with large funnel-shaped flower" .)