HODL
Crypto slang (originating from a typo of "hold") for a strategy of holding cryptocurrency long-term regardless of market swings.
See also
ATH (All-Time High)
The highest price an asset has ever reached over its entire trading history.
FOMO
Fear of Missing Out — the emotional state in which an investor buys an asset near the top of a rally out of fear of "missing the move," which often leads to losses.
FUD
Fear, Uncertainty and Doubt — the spread of negative or alarming information about a project, often deliberate, intended to push its price down.
Whale
An investor or wallet holding a very large amount of cryptocurrency. The actions of whales (large buys or sells) can noticeably move an asset's price.
Halving
A programmed event in the Bitcoin network (and some other coins) where the block reward paid to miners is cut in half. It happens roughly once every four years.
Hard fork
A backwards-incompatible change to a blockchain's protocol that splits the network into an old and a new chain (example: the split of Bitcoin and Bitcoin Cash).