'Reaction wheel' definitions:

Definition of 'Reaction wheel'

From: GCIDE
  • Reaction \Re*ac"tion\ (r[-e]*[a^]k"sh[u^]n), n. [Cf. F. r['e]action.]
  • 1. Any action in resisting other action or force; counter tendency; movement in a contrary direction; reverse action. [1913 Webster]
  • 2. (Chem.) The mutual or reciprocal action of chemical agents upon each other, or the action upon such chemical agents of some form of energy, as heat, light, or electricity, resulting in a chemical change in one or more of these agents, with the production of new compounds or the manifestation of distinctive characters. See {Blowpipe reaction}, Flame reaction, under Blowpipe, and Flame. [1913 Webster]
  • 3. (Med.) An action induced by vital resistance to some other action; depression or exhaustion of vital force consequent on overexertion or overstimulation; heightened activity and overaction succeeding depression or shock. [1913 Webster]
  • 4. (Mech.) The force which a body subjected to the action of a force from another body exerts upon the latter body in the opposite direction. [1913 Webster]
  • Reaction is always equal and opposite to action, that is to say, the actions of two bodies upon each other are always equal and in opposite directions. --Sir I. Newton (3d Law of Motion). [1913 Webster]
  • 5. (Politics) Backward tendency or movement after revolution, reform, or great progress in any direction. [1913 Webster]
  • The new king had, at the very moment at which his fame and fortune reached the highest point, predicted the coming reaction. --Macaulay. [1913 Webster]
  • 6. (Psycophysics) A regular or characteristic response to a stimulation of the nerves. [Webster 1913 Suppl.]
  • 7. An action by a person or people in response to an event. The reaction may be primarily mental (" a reaction of surprise") but is usually manifested by some activity. [PJC]
  • Reaction time (Physiol.), in nerve physiology, the interval between the application of a stimulus to an end organ of sense and the reaction or resulting movement; -- called also physiological time.
  • Reaction wheel (Mech.), a water wheel driven by the reaction of water, usually one in which the water, entering it centrally, escapes at its periphery in a direction opposed to that of its motion by orifices at right angles, or inclined, to its radii. [1913 Webster]

Definition of 'reaction wheel'

From: GCIDE
  • Water wheel \Wa"ter wheel`\
  • 1. Any wheel for propelling machinery or for other purposes, that is made to rotate by the direct action of water; -- called an overshot wheel when the water is applied at the top, an undershot wheel when at the bottom, a breast wheel when at an intermediate point; other forms are called reaction wheel, vortex wheel, {turbine wheel}, etc. [1913 Webster]
  • 2. The paddle wheel of a steam vessel. [1913 Webster]
  • 3. A wheel for raising water; a noria, or the like. [1913 Webster]