(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.

One or more observers in an area of interest.

present participle of ground truth

(computing) In machine learning, the process of gathering objective (provable) data in order to test the system.

(idiomatic, often followed by for) To prepare or create favorable conditions (for something), especially with the intent of improving public acceptance of the forthcoming occurrence.

plural of ground clearance