American Heritage® Dictionary of the English Language, Fourth Edition
- n. A simple machine consisting essentially of a wheel with a grooved rim in which a pulled rope or chain can run to change the direction of the pull and thereby lift a load.
- n. A wheel turned by or driving a belt.
Century Dictionary and Cyclopedia
- n. Properly, a simple machine consisting of a wheel having a grooved rim for carrying a rope or other line, and turning in a frame, which, when movable, is termed a pulley-block.
- n. A block containing several grooved wheels.
- n. A tackle or apparatus consisting of one or more pulley-blocks with a rope or ropes reeved through them for use in hoisting. The pulley serves to balance a great force against a small one; its sole use is to produce equilibrium; it does not save work, unless indirectly in some unmechanical way. The pulley is a lever with equal arms; but when it turns, the attachments of the forces are moved. Fig. 1 shows a fixed pulley. The equal weights d and e are in equilibrium, because they hang from the equal arms of the lever ab, having its fulcrum at c. Fig. 2 illustrates the principle of the movable pulley. The equal-armed lever, with fulcrum at c, has on one arm the weight d and on the other the force of the stretched string be. If there is equilibrium, this force must be equal to the weight of d. Thus, the total downward pull on f, one arm of the equal-armed lever fg, with fulcrum at h, is twice the weight of d, which must, therefore, be the weight of i to keep it in balance. We may also use the axiom that when a cord is free to move along its length it must be under equal stress in all its parts. Consequently, when a movable block is supported by a number of parallel parts of the same cord, these must bear equal shares of the load. Thus, in fig. 3, the lower block with the weight b brings equal strains upon four stretches of the cord, one of which is balanced by adjective Consequently, the weight of b is four times that of adjective But the effects of friction and of the stiffness of the cord are of great importance in the calculation of the advantages of pulleys. There is a great mechanical advantage in having separate blocks for all the movable pulleys, as in figs. 4 and 5. Thus, in fig. 4, the weight a is balanced over the lowest pulley by the pull on b, and the sum of these forces drawing down the lowest pulley is balanced over the second pulley by the pull on c, which is therefore double the weight at b. Thus, by means of four pulleys a balances a + 2a + 4a + 8a = a (2—1), or fifteen times instead of (as by the arrangement of fig. 3) only four times its own weight. Another arrangement is shown in fig. 5. Here, by means of four pulleys, a balances eight times its own weight.
- n. In anatomy: A trochlea, or trochlear surface of an articulation.
- n. A ligamentous loop which confines or changes the direction of the tendon of a muscle passing through it: as, the digastric muscle of the chin and the superior oblique of the eye both pass through a pulley. See cuts under muscle and eye.
- To raise or hoist with a pulley.
- n. A pulley which merely tightens the belt but takes off no power.
- n. A pulley built up of segments or sectors.
- n. A segmental pulley; a pulley made in two or more sectors for convenience in casting.
- n. One of the simple machines; a wheel with a grooved rim in which a pulled rope or chain will lift an object (more useful when two or more pulleys are used together such that a small force moving through a greater distance can exert a larger force through a smaller distance).
- v. transitive To raise or lift by means of a pulley.
GNU Webster's 1913
- n. (Mach.) A wheel with a broad rim, or grooved rim, for transmitting power from, or imparting power to, the different parts of machinery, or for changing the direction of motion, by means of a belt, cord, rope, or chain.
- v. rare To raise or lift by means of a pulley.
- n. a simple machine consisting of a wheel with a groove in which a rope can run to change the direction or point of application of a force applied to the rope
- From Middle English polley, pullie, from Old French poulie, polie ("a pulley"), (compare Medieval Latin polea, polegia, polegium; Middle Dutch puleye), of Germanic origin, from or related to Middle Low German pulen ("to pull"), Old English pullian ("to pull") . More at pull. (Wiktionary)
- Middle English poley, from Old French polie and from Medieval Latin poliva, both ultimately from Greek polos, axis; see kwel-1 in Indo-European roots. (American Heritage® Dictionary of the English Language, Fourth Edition)
“The double-line pull uses a snatch block (also known as a pulley block) to run the wire rope out to an anchor and then double it back to the vehicle, where the hook is attached to the frame -- not the bumper, winch, or any part of the suspension.”
“Fixed to the pulley was a long rope, which was hand-held.”
“And ye are prepared for the building of God the Father, and ye are raised up on high by the instrument of Jesus Christ, which is the cross; and ye are drawn by the rope, which is the Holy Spirit; and your pulley is your faith, and your love is the way which leadeth up on high to God.”
“-- In the _rope_ and _pulley_ note that when the pulley is a fixed one, the only advantage is a changed direction of the rope.”
“Across the batten hung a pulley and over the pulley was a rope.”
“But, when treating of a grave subject, what can be more silly or indecorous than such language as the following -- "Ye are raised on high by the engine of Jesus Christ, which is the cross, and ye are drawn by the rope, which is the Holy Ghost, and your pulley is your faith.”
“The pulley is the only part of the assembly that had to be drawn in two dimensions as a project requirement.”
“Abruptly she caught the human's and kender's innocent expressions, and she realized that the gully dwarf couldn't possibly be talking about the same kind of pulley job.”
These user-created lists contain the word ‘pulley’.
A list of words that are odd or words that I have looked up.
includes words of the "Prodcom list"
abducens.....draw..., ablation.....carr..., acetylcholine......., adrenalin.....nea..., afferent.....to c..., agnosia.....no kn..., alar.....wing-like, alexia.....no words, alveus.....canal, amacrine.....no l..., ambidextrous........, ambiguus.....doub... and 701 more...
I will also accept mechanisms, machine elements, contrivances, and engines.
machine, machines, Machine, Machines, Rage Against the ..., machine quilting, simple machine, Turing machine, turing machine, machine element, the heart-attack ..., ghost in the machine and 34 more...
Just what it says. Archery rocks.
Amusingly-named mechanical and electrical parts to be found in a particular warehouse in Newfoundland
Looking for tweets for pulley.