Carelessly dropped rubbish (6)
I believe the answer is:
litter
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">carelessly dropped rubbish</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for litter that I've seen before include "Animal young, stretcher and rubbish" , "Carelessly dropped rubbish" , "New-born animals" , "Scatter rubbish around" , "Not a neat" .)