Leaves the bar, oddly (3)
I believe the answer is:
tea
'leaves' is the definition.
(as in tea leaves)
'the bar oddly' is the wordplay.
'oddly' means one should take alternating letters (letters in the odd-numbered positions are used).
'the'+'bar'='thebar'
The alternating letters of 'thebar' are 'TEA'.
(Other definitions for tea that I've seen before include "Infusion of dried leaves" , "Assam, for instance" , "Oolong, for example" , "Strangely, one may eat this drink" , "Principally" .)