At full speed (4,3)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">at full speed</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 flat out that I've seen before include "Exhausted - at full speed" , "At top speed or effort - being horizontal?" , "At top speed; intense (effort)" , "Lying on floor" , "very quickly?" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">at full speed</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 amain that I've seen before include "force" , "with violence" , "at great speed" , "powerfully poetic" , "violently" .)