Left a can of tongue (5)
I believe the answer is:
latin
'tongue' is the definition.
(Latin is an example)
'left a can' is the wordplay.
'left' becomes 'l' (common abbreviation).
'can' becomes 'tin' (both are metal containers).
'l'+'a'+'tin'='LATIN'
'of' is the link.
(Other definitions for latin that I've seen before include "Language of old 8 down" , "Language of the Caesars" , "ancient tongue" , "Hispanic, for example" , "Cicero's tongue" .)