Tiers (4)
I believe the answer is:
rows
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">tiers</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 rows that I've seen before include "Arrangements side by side in lines" , "Puts one's oar in" , "Angry disputes" , "Columns" , "Arguments" .)