Classical language in mine is expanding (8)
I believe the answer is:
dilating
'expanding' is the definition.
The definition and answer can be both related to change as well as being present participle verbs.
Maybe you can see a link between them that I can't see?
'classical language in mine' is the wordplay.
'classical language' becomes 'latin' (I've seen this before).
'in' means one lot of letters goes inside another.
'mine' becomes 'dig' (I've seen this before).
'latin' placed within 'dig' is 'DILATING'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for dilating that I've seen before include "Swelling out or enlarging" , "Swelling or expanding" , "Becoming expansive" , "Becoming wider" .)