The Terrorist Identities Datamart Environment (TIDE) is the U.S. Government's central database on known or suspected international terrorists, and contains classified information provided by members of the Intelligence Community such as CIA, DIA, FBI, NSA, and many others.

Tidal is the adjectival form of the word tide.

Tides are the rise and fall of sea levels caused by the combined effects of gravitational forces exerted by the Moon, Sun, and rotation of the Earth.