Complete and utter (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">complete and utter</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for sheer that I've seen before include "Very fine or vertical" , "Very steep or diaphanous" , "Very thin and fine" , "Very thin; unmitigated" , "Unqualified" .)
(Other definitions for arrant that I've seen before include "Out-and-out, utter" , "Downright - maybe nonsense" , "Downright - notorious" , "Utter and extreme, maybe nonsense" , "Utter, complete" .)