Small bottle line announced (5)
I believe the answer is:
phial
'small bottle' is the definition.
(I've seen this before)
'line announced' is the wordplay.
'line' becomes 'file' (file is a kind of line).
'announced' shows a homophone (sound like).
'file' sounds like 'PHIAL'.
(Other definitions for phial that I've seen before include "Small bottle for liquids" , "Small bottle (containing a drug)" , "Small bottle for potions etc" , "Ampoule" , "Small glass bottle for perfume or medicine" .)