Credit cards (7)
I believe the answer is:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">credit cards</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 plastic that I've seen before include "non-metallic material" , "means of deferring payment" , "Scalp it badly to make a synthetic material" , "Fashionable - substitute for wood or metal" , "Clasp it (anag.)" .)