block (redirected from Atrioventricular block, second degree)
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Related to Atrioventricular block, second degree: Third degree heart block
2. a casing housing one or more freely rotating pulleys
a. interference in the normal physiological functioning of an organ or part
4. Psychol a short interruption of perceptual or thought processes
5. Computing a group of words treated as a unit of data on a tape, disk, etc
7. Cricket a mark made near the popping crease by a batsman to indicate his position in relation to the wicket
A large piece of stone, taken from the quarry to the mill for sawing and further working.
(1) A unit of a mechanism in the form of a wheel with a groove around its circumference over which a cable or chain is drawn. It is used to change the direction of a tractive force and to obtain a force or velocity advantage; more rarely, to transfer a torque. Depending on their function, blocks are known as guide, balance, runner, and driving (for imparting rotary motion to a shaft) pulleys. In order to achieve a large force or velocity advantage, a lifting mechanism made up of a combination of blocks (a block and tackle) is used.
(2) A subassembly of a machine, consisting of several identical parts, such as a block of cylinders in an internal combustion engine or the spindle block in a multiple-spindle machine.
(3) A stone (concrete or ceramic) of large size (appreciably larger than a brick) used in the construction of buildings and for road surfacing.
A group of information units (such as records, words, characters, or digits) that are transported or considered as a single unit by virtue of their being stored in successive storage locations; for example, a group of logical records constituting a physical record.
The section of a computer memory or storage device that stores such a group of information units. Also known as storage block.
To combine two or more information units into a single unit.
A contiguous group of text characters that is marked for moving, copying, saving, deletion, or some other word-processing operation.
A metal or wood case enclosing one or more pulleys; has a hook with which it can be attached to an object.
A division of a mine, usually bounded by workings but sometimes by survey lines or other arbitrary limits.
In quarrying, a large portion of rock that is removed from the quarry as a solid mass for further processing at a mill.
The subdivision of a sea area for the licensing of oil and gas exploration and production rights.
In experimental design, a homogeneous aggregation of items under observation, such as a group of contiguous plots of land or all animals in a litter.
2. (Brit.) A walling unit which exceeds in length, width, or height the dimensions specified for a brick.
3. A solid piece of wood or other material.
4. A plank or timber which serves as bridging between joists or the like.
5. In quarrying, the large piece of stone, generally squared, that is taken from the quarry to the mill for sawing, slabbing, and further working.
6. A mechanical
block(1) A group of disk or tape records that is stored and transferred as a single unit. On a CD, a block consists of 98 frames of 33 bytes for a total of 3,234 bytes, or 1/75th of a second. See block level.
(2) A group of bits or bytes that is transmitted or processed as a single unit.
(3) A group of text characters that has been marked for moving, copying, saving or other operation.
(4) A rectangular group of pixels that are processed as a unit.
(5) A group of program statements that are treated as a unit based on the results of a comparison.