bore

bore, inrush of water that advances upstream with a wavelike front, caused by the progress of incoming tide from a wide-mouthed bay into its narrower portion. The tidal movement tends to be retarded by friction as it reaches the shallower water and meets the river current; it therefore piles up and forms a low wall of water that moves upstream with considerable force and velocity as the tide continues to rise. In the mouth of the Amazon River a tidal bore known locally as the pororoca occurs every spring tide. It has a wall of water from 5 to 15 ft (1.5–4.6 m) high and advances at a speed of from 10 to 15 mi (16–24 km) per hr. The highest recorded bore (15 ft/4.6 m) is found in the Fuchun River near Hangzhou, China. Bores are found also in the Bay of Fundy, in Solway Firth, in the Severn, Seine, and Hugli rivers, and in Hangzhou Bay.

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bore¹

a. a circular hole in a material produced by drilling, turning, or drawing

b. the diameter of such a hole

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bore²

a high steep-fronted wave moving up a narrow estuary, caused by the tide

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bore [bȯr]

(design engineering)

Inside diameter of a pipe or tube.

(mechanical engineering)

The diameter of a piston-cylinder mechanism as found in reciprocating engines, pumps, and compressors.

To penetrate or pierce with a rotary tool.

To machine a workpiece to increase the size of an existing hole in it.

(mining engineering)

A tunnel under construction.

To cut or drill a hole for blasting, water infusion, exploration, or water or firedamp drainage.

(oceanography)

A high, breaking wave of water, advancing rapidly up an estuary. Also known as eager; mascaret; tidal bore.

A submarine sand ridge, in very shallow water, whose crest may rise to intertidal level.

(ordnance)

The interior of a gun barrel or tube.