HODL, is a unique terminology or meme within the crypto community. And it refers to the act of hodling or holding a cryptocurrency over an extended period. Often used as a strategy in hopes of seeing the price increase. It originated in a post on the Bitcoin Forum message board by an apparently inebriated user who posted with a typo in the subject, “I AM HODLING.
Guide on crypto lingo like HODL and 40 more can be found here.