| 释义 |
con·stant
I. \ˈkänztənt, -n(t)st-\ adjective
Etymology: Middle English, from Middle French, from Latin constant-, constans, present participle of constare to stand firm, be consistent, from com- + stare to stand — more at stand
1. : marked by firmness, steadfastness, resolution, or faithfulness : not weak, yielding, vacillating, or disloyal
< a man constant in adherence to his ideals >
< a constant friend >
2. : fixed and invariable
< the content of constitutional immunities is not constant but varies from age to age — B.N.Cardozo >
: remaining unchanged : steady, uniform
< a constant-flow calorimeter >
3. : marked by continual recurring or by regular occurrence, operation, or manifestation
< their aims and their methods have been subject to constant scrutiny, not only by professionals, but also by parents and citizens — J.B.Conant >
< the children running in and out of the house were a constant annoyance >
4. obsolete : firm and steady : immovable, solid
5. obsolete : confident in opinion : positive, certain
Synonyms: see continual, faithful, steady
II. noun
(-s)
1. : something that does not vary or change in its relationship or in an essential relationship with other things
< the one constant in all this is that each page is indelibly marked with personality — E.A.Weeks >
< the environment should be the constant; the individual, the variable — W.H.Whyte >
as
a. : an abstract number or a physically dimensional quantity having a fixed or approximately fixed value (as in a situation or throughout the operation concerned) and being sometimes universal and permanent (as the circular ratio π or the constant of gravitation) or sometimes characteristic of some substance or instrument (as the refractive index of an optical glass or the sensitivity of a galvanometer)
b. : a magnitude in mathematics that is assumed not to change its value in a certain discussion, process, or stage of investigation — opposed to variable
c. : a term in logic with an invariant denotation : a symbol with fixed designation (as a connective, quantifier, or parenthesis) — contrasted with variable
d. : a kind of plant or animal (as a species or variety) that is regularly present in a particular ecological community (as an association)
2. : a secondary-school subject considered of such basic importance that it is required of all pupils |