Denshi Jisho — Online Japanese dictionary

コップ 1: glass (i.e. drinking vessel) (dut: Kop); tumbler;
2: (Slang) cop (police officer)
Common word, Noun 
コップ コップざけ sake sold in a cup rather than a bottle; drinking sake from a regular-size cup rather than from a small sake cup
Noun 
コップの中の嵐 コップのなかのあらし storm in a teacup
Expression 

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