1. | pricingHighest historic price an asset has been traded at.
2. | informationThe All Time High usually refers to a price held over some amount of time. Since the price of a coin can drastically fluctuate in the short term, the all time high is usually regarded as the highest sustained price of an asset over a minimum period of multiple hours or days.
2.1 | BCH - Coinbase day
The day Bitcoin Cash (BCH) was listed on Coinbase for trading, its value surged up to $3,715.91 USD. But during that surge there were spikes where the price reached $7,000, and even $9,000 for a few seconds.
As these spikes were temporary anomalies on a particular exchange, they are often not considered the All Time High. But it depends who you ask.
* All terms and definitions will change as the Cryptionary improves