ATL

The term "all-time low" (ATL) refers to the lowest price an asset (stock, currency) has ever reached on an exchange. In relation to cryptocurrencies, this means that the price of a certain cryptocurrency has broken all its past records and is trading at its lowest price ever. 

Exactly the opposite of the ATL would be the ATH. The All Time High (ATH) stands for the highest price ever recorded for a quotation.