Drink, hot, acceptable in tube (6)
I believe the answer is:
siphon
'tube' is the definition.
(siphon is a kind of tube)
'drink hot acceptable' is the wordplay.
'drink' becomes 'sip' (I've seen this before).
'hot' becomes 'h'.
'acceptable' becomes 'on' (I've seen this in other clues).
'sip'+'h'+'on'='SIPHON'
'in' acts as a link.
(Other definitions for siphon that I've seen before include "Drawing device" , "Draw off (liquid) by pipe" , "Tube taking fluid from higher to lower point" , "Squirting bottle found in shop" , "A bottle that squirts, say soda water" .)