Hawaiian garland that is left over (3)
I believe the answer is:
lei
'hawaiian garland' is the definition.
(I've seen this before)
'that is left over' is the wordplay.
'that is' becomes 'ie' ('i.e.' can be a synonym of 'that is'**).
'left' becomes 'l' (common abbreviation).
'over' is a reversal indicator.
'ie'+'l'='iel'
'iel' backwards is 'LEI'.
(Other definitions for lei that I've seen before include "Hawaiian necklace of flowers" , "Band of flowers" , "Hawaiian wreath" , "Bloomers on line" , "Hawaiin flower garland" .)