Med lab specimen (4)

I believe the answer is:
swab
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">med lab specimen</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for swab that I've seen before include "Surgical cleaner" , "Clean (a wound)" , "Cleaning implement" , "Mop; surgical pad" , "Wound-cleaner" .)