The other day I was reading an interesting article about dinosaurs when I came across to the phrase Rip Off. I looked it up in the dictionary but none of the definitions there turned out to be suitable to make the meaning of the sentence I encountered sensible. I have quoted part of that article's paragraph here. Please if you know the meaning write it here giving a reference unless you are a native English speaker.
Thanks in advance.

the exact paragraph: "I realized when I read the New York Times article and saw Mary Schweitzer's story of having uncovered this dinosaur that this is exactly the sort of thing that would appeal to John and hence ripped him off an e-mail from my Blackberry," Cantley said. "John of course took the bait." Schweitzer readily agreed to provide T. rex bone samples. "She knew from our last collaboration that I was not going to stop until I found something," Asara said.

If you are interested in the whole article follow the link below:

http://web.med.harvard.edu/sites/RELEASES/html/TRex.html

the definitions in the dictionary are: (Longman Dictionary of Contemporary English)

rip somebody/something ↔ off phrasal verb

1-to charge someone too much money for something
ￚsynonym overchargeThe agency really ripped us off.
2-to steal something
Somebody had come in and ripped off the TV and stereo.
3-to take words, ideas etc from someone else's work and use them in your own work as if they were your own ideas
synonym: plagiarize

thanks for your clarifying answer Clive. It was helpful.

 I had infered the same meaning as you mentioned from the context but i was wondering whay non of the well thought of dictionaries has included this meaning?

best wishes