pass(redirected from let pass)
Also found in: Dictionary, Thesaurus, Medical, Legal, Idioms.
pass,opening or way by which a natural or artificial barrier can be crossed. The term pass is usually applied to a relatively narrow passage through a mountainous region. A pass, like an isthmus, may have great strategic and economic importance; the history of a nation has often been determined by its success or failure in defending a pass, and land trade routes must necessarily cross passes. In the Alps, Saint BernardSaint Bernard,
two Alpine passes, both used since antiquity. The Great Saint Bernard (alt. 8,110 ft/2,472 m), on the Italian-Swiss border, links Valais canton, Switzerland, with Valle d'Aosta, Italy.
..... Click the link for more information. , SimplonSimplon
, pass, 6,590 ft (2,009 m) high, in the Lepontine Alps, Valais canton, S Switzerland. It is crossed by the Simplon Road built (1800–1806) by Napoleon I.
..... Click the link for more information. , and Saint GotthardSaint Gotthard
, mountain group of the Lepontine Alps, S central Switzerland, rising to Pizzo Rotondo (10,472 ft/3,192 m high). The Reuss, Rhine, Ticino, and Rhône rivers rise there. It is crossed by the Saint Gotthard Pass, 6,935 ft (2,114 m) high.
..... Click the link for more information. are important; in the Caucasus, DaryalDaryal
, pass, c.3,950 ft (1,204 m) high, N Georgia, in the central Greater Caucasus Mts. below Mt. Kazbek. Situated above the Terek River, it is noted for its wild grandeur.
..... Click the link for more information. is traversed by a great military road; in Asia, Khyber PassKhyber Pass
, narrow, steep-sided pass, 28 mi (45 km) long, winding through the Safed Koh Mts., on the Pakistan-Afghanistan border; highest point is 3,500 ft (1,067 m). The routes through it link the cities of Peshawar, Pakistan, and Kabul, Afghanistan.
..... Click the link for more information. into India and the passes of the Himalayas, KarakorumKarakorum
mountain range, extending c.300 mi (480 km), between the Indus and Yarkant rivers, N Kashmir, S central Asia; SE extension of the Hindu Kush. It covers disputed territory, held by China on the north, India on the east, and Pakistan on the west.
..... Click the link for more information. , and other ranges are important.
a gap formed by the grooves of two coupled rolls through which the metal to be reduced is passed in order to give it the required shape.
A distinction is made between reducing, roughing, and finishing passes. Reducing passes serve to reduce the cross section of the initial stock without significant alteration of its shape; roughing passes are used to produce rolled metal with a cross section close to that of the finishing stage; and finishing passes are used to give the metal its final shape and dimensions.