Draw off one posh concoction around noon (6)
I believe the answer is:
siphon
'draw off' is the definition.
(I've seen this in another clue)
'one posh concoction around noon' is the wordplay.
'one' becomes 'i' (Roman numeral).
'concoction' indicates an anagram.
'around' is an insertion indicator.
'noon' becomes 'n' (abbreviation for noon).
'posh' anagrammed gives 'spho'.
'i' inserted into 'spho' is 'sipho'.
'sipho'+'n'='SIPHON'
(Other definitions for siphon that I've seen before include "A bottle that squirts, say soda water" , "Tube used to remove liquid from a higher to a lower level" , "On ship (anag)" , "Soda dispenser" , "Draw off (liquid) by pipe" .)