Two pints then eight emptied, or four (7)
I believe the answer is:
quartet
'four' is the definition.
(synonyms)
'two pints then eight emptied' is the wordplay.
'two pints' becomes 'quart' (unit of liquid equal to two pints).
'then' says to put letters next to each other.
'emptied' says to hollow out the word (remove centre letters).
'eight' with its middle taken out is 'et'.
'quart'+'et'='QUARTET'
'or' is the link.
(Other definitions for quartet that I've seen before include "[COMPOSITION]" , "Group of four musicians" , "A pair of braces" , "like a string one?" , "Four musicians playing together" .)