By the sound of it, white container for liquid (4)
I believe the answer is:
pail
'container for liquid' is the definition.
I can't judge whether this defines the answer.
'by the sound of it white' is the wordplay.
'by the sound of it' shows a homophone (sound like).
'white' becomes 'pale' (I've seen this before).
'pale' sounds like 'PAIL'.
Can you help me to learn more?
(Other definitions for pail that I've seen before include "Open-topped container" , "Container; sounds like dim" , "Water carrier" , "water-carrier" , "Vessel for carrying liquids" .)