|a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question.|
|a screen or mat covered with a dark material for shielding a camera lens from excess light or glare.|
|turbine (ˈtɜːbɪn, -baɪn)|
|reaction turbine impulse turbine See also gas turbine any of various types of machine in which the kinetic energy of a moving fluid is converted into mechanical energy by causing a bladed rotor to rotate. The moving fluid may be water, steam, air, or combustion products of a fuel|
|[C19: from French, from Latin turbō whirlwind, from turbāre to throw into confusion]|
|turbine (tûr'bĭn, -bīn') Pronunciation Key
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Any of various machines in which the kinetic energy of a moving fluid, such as water, steam, or gas, is converted to rotary motion. Turbines are used in boat propulsion systems, hydroelectric power generators, and jet aircraft engines. See also gas turbine.