9 across
2
sat
wagging
tongue
(9)
2 sat wagging tongue (9)
hints
0
checks
0
hints
The definition is at the end of the clue.
How the clue works
tongue here is your definition — a language. Now, "2" is a cross-reference to 2 down (the answer being OPENER), and you take that together with sat to get the letters OPENERSAT. wagging tells you to anagram those nine letters, and sure enough they scramble neatly into your answer.