Grammatical rules (6)
I believe the answer is:
syntax
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">grammatical rules</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 syntax that I've seen before include "branch of linguistics" , "Grammatical rules" , "The rules governing the arranging of words" , "Way in which words are arranged to form sentences" , "The rules governing words arrangements" .)