Jam pot (3)
I believe the answer is:
jar
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">jam pot</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 jar that I've seen before include "Glass of beer; clash" , "Grate" , "Enduring courage" , "Jolt with glass container" , "Wide-mouthed vessel" .)