Okey-dokey (6)
I believe the answer is:
righto
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">okey-dokey</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for righto that I've seen before include "Agreed" , "Okey-dokey" , "very well" , "Correct" , "Informal expression of agreement or acceptance" .)