A pump in cryptocurrency trading refers to a sharp, rapid increase in the price of a cryptocurrency, often driven by coordinated buying activity. This price surge is usually artificial and may be followed by a dump, where the price quickly drops as those involved in the pump sell off their holdings to take profits.

This tactic is often part of a "pump-and-dump" scheme, where a group of traders or individuals attempt to inflate the price of a low-market-cap cryptocurrency by creating hype, encouraging others to buy in, and then selling their own holdings at the higher price. Once they sell, the price crashes, leaving unsuspecting investors with losses.

While pumps can sometimes happen naturally due to positive news or market events, coordinated pump-and-dump schemes are considered unethical and are often illegal in regulated financial markets. However, they can be more common in less regulated areas of the cryptocurrency market.