Dickens swallows old English drink (5)
I believe the answer is:
booze
'drink' is the definition.
(booze is a kind of drink)
'dickens swallows old english' is the wordplay.
'dickens' becomes 'boz' (I've seen this in another clue).
'swallows' is an insertion indicator.
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'english' becomes 'E' (abbreviation).
'boz' enclosing 'o' is 'booz'.
'booz'+'e'='BOOZE'
(Other definitions for booze that I've seen before include "Drink alcohol" , "Alcohol (sl.)" , "In slang, alcoholic drink" , "plonk?" , "Drink too much (colloq.)" .)