カンニング("cunning") means "to cheat," as in to "cheat on a test." カンニング is a loan word from the English word "cunning," but in English, the word "cunning," carries a different definition. "Cunning" is usually used as an adjective that is to describe someone who is clever in a deceptive way.
Although the use of katakana for the word カンニング is obvious, it is interesting that the original meaning of "cunning" was adapted differently to a new definition: "to cheat on a test."