(aviation) The halting of air traffic for a particular airport, with no arrivals allowed and all departures held on the ground.

plural of ground game

(Britain, law, uncountable) Rabbits and hares / (martial arts) Hand-to-hand combat in which both fighters are on the ground, or skill in such combat / (golf) Putting; hitting the ball along the ground

A cemetery or graveyard.

(geology) An effect of seismic activity, such as an earthquake, where the ground becomes very soft, due to the shaking, and acts like a liquid, causing landslides, spreading, and settling.

(military) A large area of firm ground, formerly usually adjacent to fortifications and now usually a paved area at a military base, where soldiers present themselves for inspection ("parade") and practice marching and close-order drills.

(idiomatic, uncountable, usually with "the") A position of advantage or superiority in a conflict or competition. / Used other than figuratively or idiomatically: see high, ground.

simple past tense and past participle of grind down

To gather information by direct observation rather than inference.

Information acquired by direct observation rather than by inference.