Small jug and pipe (5)
I believe the answer is:
sewer
'pipe' is the definition.
(sewer is a kind of pipe)
'small jug' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'jug' becomes 'ewer' (type of vessel).
's'+'ewer'='SEWER'
'and' is the link.
(Other definitions for sewer that I've seen before include "Plier of needle; drain" , "One working with material?" , "Filthy channel" , "Waste-pipe" , "One plying needle; drain" .)