British language (5)
I believe the answer is:
welsh
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">british language</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for welsh that I've seen before include "Native to, eg, Cardiff" , "Default on bet in Wales?" , "Leave without paying" , "tongue" , "- Dresser; - rarebit; - harp" .)