The language of Somerset? (4)

I believe the answer is:

erse

'the language' is the definition.
(historical term for Scottish Gaelic)

'of somerset' is the wordplay.
'of' indicates a hidden word.
'ERSE' is hidden within 'somerset'.

(Other definitions for erse that I've seen before include "Name sometimes given to languages of the Celts in Ireland and Scotland" , "Old language spoken by strange seer" , "Old Celtic language" , "Old Scots or Irish Gaelic" , "Celtic tongue" .)

I've seen this clue in The Globe and Mail and The Telegraph.

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