Flat circular object (4)
I believe the answer is:
disc
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">flat circular object</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 disc that I've seen before include "Sound recording" , "Layer of cartilage between spinal vertebrae" , "Body without limbs" , "Record, CD" , "Old record" .)