Simultaneously freebooting someone else's video, claiming it for your own, while also humblebragging about its greatness.
Random Person 1: Man, my video about the American Empire only has 1.4 million views. How frustrating.
Random Person 2: 1.4 million views is awesome, and it's not even your video! It's CGP Grey's! Stop humblejacking, you chump.
by Boondoggy July 16, 2014
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Lowering expectations to make yourself seem more humble when you do succeed by complaining about how bad you are.
Grey: I wish I had a couple more years to edit this video and do more research. It is so terrible.
Brady: Stop humblejacking, we all know everybody will love it.
by Pop2323pop September 07, 2014
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