Row or level (4)
I believe the answer is:
tier
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">row</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(a tier is a row of things)</span><br/ ><br/ >'<span class="explanation-format__original">level</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ ></span>
(Other definitions for tier that I've seen before include "Level - layer" , "Rite (anag.)" , "Storey" , "Person joining" , "Rite about layer" .)