Often used to designate something of major size and importance.
Grand Canyon a deep gorge in Arizona, formed by the Colorado River, which is about 440 km (277 miles) long, 8 to 24 km (5 to 15 miles) wide, and, in places, 1,800 m (6,000 ft) deep. Grand Canyon State is an informal name for Arizona.
Grand Fleet the main British naval fleet, either that based at Spithead in the 18th century or that based at Scapa Flow in the First World War.
Grand Guignol a dramatic entertainment of a sensational or horrific nature, originally a sequence of short pieces as performed at the Grand Guignol theatre in Paris. From the name of the bloodthirsty puppet Guignol.
Grand National an annual horse race established in 1839, a steeplechase run over a course of 4 miles 856 yards (about 7,200 metres) with thirty jumps, at Aintree, Liverpool, in late March or early April.
Grand Prix (de Paris) an international horse race for three-year-olds, founded in 1863 and run annually in June at Longchamps, Paris.
grand slam the winning of each of a group of major championships or matches in a particular sport in the same year, in particular in tennis, golf, or rugby union; grand slam here is a transferred use from cards, especially bridge, referring to the bidding and winning of all thirteen tricks.
grand tour a cultural tour of Europe conventionally undertaken, especially in the 18th century, by a young man of the upper classes as a part of his education.