Crossword Genius

Friend shot back in very old British language (7)

Ross

I believe the answer is:

volapuk

I'm a little stuck... Click here to teach me more about this clue!

'language' is the definition.
(I know that Volapuk is a type of artificial language)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Another definition for volapuk that I've seen is " tongue made!".)

I've seen this clue in The Guardian.
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