time
caesium clock:
a type of atomic clock that uses the frequency of radiation absorbed in changing the spin of electrons in caesium atoms.
See also second (below).
second:
1. 1/60 of a minute of time.
2. the basic SI unit of time: the duration of 9 192 631 770 periods of radiation corresponding to the transition between two hyperfine levels of the ground state of caesium-133. Symbol: s.
space-time:
Also called "space-time continuum," the four-dimensional continuum, having three spatial coordinates and one temporal coordinate, in which all physical quantities may be located.
See more definitions at Dictionary.com. *
unity:
1. one of the three principles of dramatic structure (the three unities) derived from Aristotelian aesthetics and formalized in the neoclassic canon in which a play is required to represent action as taking place in one day (unity of time), as occurring within one place (unity of place), and as having a single plot with a beginning, middle, and end (unity of action).
Origin:
before 900; (noun) Middle English; Old English tīma; cognate with Old Norse tīmi; (verb) Middle English timen to arrange a time, derivative of the noun; akin to tide1. British dictionary: Old English tīma; related to Old English tīd time, Old Norse tīmi, Alemannic zīme; see tide 1. —Dictionary.com.
First Known Use of time: Noun: before the 12th century. Verb: 14th century. Adjective: circa 1711. History and Etymology for time: Noun: Middle English, from Old English tīma; akin to Old Norse tīmi time, Old English tīd — more at tide entry 3. —Merriam-Webster.
Sources: 1, 2.
a type of atomic clock that uses the frequency of radiation absorbed in changing the spin of electrons in caesium atoms.
See also second (below).
second:
1. 1/60 of a minute of time.
2. the basic SI unit of time: the duration of 9 192 631 770 periods of radiation corresponding to the transition between two hyperfine levels of the ground state of caesium-133. Symbol: s.
space-time:
Also called "space-time continuum," the four-dimensional continuum, having three spatial coordinates and one temporal coordinate, in which all physical quantities may be located.
See more definitions at Dictionary.com. *
unity:
1. one of the three principles of dramatic structure (the three unities) derived from Aristotelian aesthetics and formalized in the neoclassic canon in which a play is required to represent action as taking place in one day (unity of time), as occurring within one place (unity of place), and as having a single plot with a beginning, middle, and end (unity of action).
Origin:
before 900; (noun) Middle English; Old English tīma; cognate with Old Norse tīmi; (verb) Middle English timen to arrange a time, derivative of the noun; akin to tide1. British dictionary: Old English tīma; related to Old English tīd time, Old Norse tīmi, Alemannic zīme; see tide 1. —Dictionary.com.
First Known Use of time: Noun: before the 12th century. Verb: 14th century. Adjective: circa 1711. History and Etymology for time: Noun: Middle English, from Old English tīma; akin to Old Norse tīmi time, Old English tīd — more at tide entry 3. —Merriam-Webster.
Sources: 1, 2.