Velociraptoring
When you feed someone learning your language a fake definition of a word or a completely made up word and definition, in the hopes that they will look silly using it publicly at a later date, and getting funny looks.
For example, tell the language learner that “I have a velociraptor in my head” means “I am really hungry” and just wait, years if necessary, until they decide to use it in conversation. The term velociraptoring originated from this being the first ever attempt at the technique.