Unit of pressure (6)
I believe the answer is:
pascal
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">unit of pressure</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 pascal that I've seen before include "French mathematician, d. 1662 - SI unit of pressure" , "Seventeenth century French physicist" , "Unit of pressure, French philosopher and programming language" , "clever thinker" , "religious philosopher" .)