Flower left at university and at home (5)
I believe the answer is:
lupin
'flower' is the definition.
(I've seen this before)
'left at university and at home' is the wordplay.
'left' becomes 'l' (common abbreviation).
'at university' becomes 'up' ('up' can mean studying at university).
'and' says to put letters next to each other.
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'l'+'up'+'in'='LUPIN'
(Other definitions for lupin that I've seen before include "Nil up in this flower" , "Fodder plant" , "9 [BLOOM]" , "Tall-spiked flower" , "Garden plant of the pea family" .)