Greek mathematician (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">greek mathematician</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 euclid that I've seen before include "Greek mathematician c. three hundred BC" , "Great Greek mathematician, notable for geometry" , "6 mathematician" , "Early Greek geometrician" , "Ancient Greek master of geometry" .)
(Other definitions for pythagoras that I've seen before include "Ay to graphs (anag) - 21 3 17 theorist" , "Greek philosopher and mathematician, d. c 500 BC" , "Greek philosopher/mathematician" , "theorem by this guy" , "Greek with a theorem" .)