Atari is a warning shout from a board game, used as the name of a video game company.
Nolan Bushnell and Ted Dabney began in 1971 as a partnership called Syzygy Engineering. Syzygy is an astronomical term for three bodies lined up. When they went to incorporate in California, they found a company already had the name.
Michael Current's copy of a 1981 Atari company magazine adds details. Larry Bryan, a former colleague, was an early partner who dropped out, and the founders tried to buy the Syzygy name without success. They also considered BD, Inc. and DB, Inc., but dropped them as too close to Black & Decker and Dun & Bradstreet.
So they turned to Go. Bushnell and Dabney both played, and the Museum of Play says Bushnell gave the state three Go terms: Sente, Atari and Hanne. How-To Geek says they were listed in order of preference. Sente means having the initiative. Hanne is a move that wraps around an opponent's stone. Atari was the one that came back approved.
In Go, atari describes a stone or group that can be captured on the next move. A player has surrounded a stone on three sides, leaving one free space. The Museum of Play compares it to "check" in chess. The Japanese word, 当たり, has other senses, such as a hit or a correct guess, according to How To Geek.
The reason Atari won out is not entirely clear. How To Geek says someone at the California Secretary of State's office apparently chose it, and that the exact reason remains unclear. The 1981 article also says the office selected Atari from the list. Bushnell has said many times that Go is his favorite game.
Atari was incorporated on June 27, 1972. Bushnell later reused the leftover term: Wikipedia says he named another company Sente Technologies. Atari Games also gave its 1987 subsidiary the Go name Tengen, which the Museum of Play translates as "the origin of heaven."