Search Result for "perpetual motion":
Wordnet 3.0

NOUN (1)

1. motion that continues indefinitely without any external source of energy; impossible in practice because of friction;


The Collaborative International Dictionary of English v.0.48:

Perpetual \Per*pet"u*al\, a. [OE. perpetuel, F. perp['e]tuel, fr. L. perpetualis, fr. perpetuus continuing throughout, continuous, fr. perpes, -etis, lasting throughout.] Neverceasing; continuing forever or for an unlimited time; unfailing; everlasting; continuous. [1913 Webster] Unto the kingdom of perpetual night. --Shak. [1913 Webster] Perpetual feast of nectared sweets. --Milton. [1913 Webster] Circle of perpetual apparition, or Circle of perpetual occultation. See under Circle. Perpetual calendar, a calendar so devised that it may be adjusted for any month or year. Perpetual curacy (Ch. of Eng.), a curacy in which all the tithes are appropriated, and no vicarage is endowed. --Blackstone. Perpetual motion. See under Motion. Perpetual screw. See Endless screw, under Screw. [1913 Webster] Syn: Continual; unceasing; endless; everlasting; incessant; constant; eternal. See Constant. [1913 Webster]
The Collaborative International Dictionary of English v.0.48:

Motion \Mo"tion\, n. [F., fr. L. motio, fr. movere, motum, to move. See Move.] 1. The act, process, or state of changing place or position; movement; the passing of a body from one place or position to another, whether voluntary or involuntary; -- opposed to rest. [1913 Webster] Speaking or mute, all comeliness and grace attends thee, and each word, each motion, forms. --Milton. [1913 Webster] 2. Power of, or capacity for, motion. [1913 Webster] Devoid of sense and motion. --Milton. [1913 Webster] 3. Direction of movement; course; tendency; as, the motion of the planets is from west to east. [1913 Webster] In our proper motion we ascend. --Milton. [1913 Webster] 4. Change in the relative position of the parts of anything; action of a machine with respect to the relative movement of its parts. [1913 Webster] This is the great wheel to which the clock owes its motion. --Dr. H. More. [1913 Webster] 5. Movement of the mind, desires, or passions; mental act, or impulse to any action; internal activity. [1913 Webster] Let a good man obey every good motion rising in his heart, knowing that every such motion proceeds from God. --South. [1913 Webster] 6. A proposal or suggestion looking to action or progress; esp., a formal proposal made in a deliberative assembly; as, a motion to adjourn. [1913 Webster] Yes, I agree, and thank you for your motion. --Shak. [1913 Webster] 7. (Law) An application made to a court or judge orally in open court. Its object is to obtain an order or rule directing some act to be done in favor of the applicant. --Mozley & W. [1913 Webster] 8. (Mus.) Change of pitch in successive sounds, whether in the same part or in groups of parts. [1913 Webster] The independent motions of different parts sounding together constitute counterpoint. --Grove. [1913 Webster] Note: Conjunct motion is that by single degrees of the scale. Contrary motion is that when parts move in opposite directions. Disjunct motion is motion by skips. Oblique motion is that when one part is stationary while another moves. Similar or direct motion is that when parts move in the same direction. [1913 Webster] 9. A puppet show or puppet. [Obs.] [1913 Webster] What motion's this? the model of Nineveh? --Beau. & Fl. [1913 Webster] Note: Motion, in mechanics, may be simple or compound. Simple motions are: (a) straight translation, which, if of indefinite duration, must be reciprocating. (b) Simple rotation, which may be either continuous or reciprocating, and when reciprocating is called oscillating. (c) Helical, which, if of indefinite duration, must be reciprocating. Compound motion consists of combinations of any of the simple motions. [1913 Webster] Center of motion, Harmonic motion, etc. See under Center, Harmonic, etc. Motion block (Steam Engine), a crosshead. Perpetual motion (Mech.), an incessant motion conceived to be attainable by a machine supplying its own motive forces independently of any action from without. According to the law of conservation of energy, such perpetual motion is impossible, and no device has yet been built that is capable of perpetual motion. [1913 Webster +PJC] Syn: See Movement. [1913 Webster]
WordNet (r) 3.0 (2006):

perpetual motion n 1: motion that continues indefinitely without any external source of energy; impossible in practice because of friction