1. verb To deceive or trick one. The student tried to dupe me with a letter on which he'd forged his mom's signature.

2. verb To copy something. Did you dupe this tape, or am I holding the only copy?

3. noun Someone who is the victim of deception or trickery. Yep, I was a dupe—they were lying to me the whole time.

4. noun Something that is a copy of something else. Do you have a dupe of this tape, or am I holding the only copy?

5. noun, slang A cosmetic item that is in some way very similar to a higher-priced one. Is this Maybelline blush really a dupe for that pricey NARS one?