(of a set) the cardinal number indicating the number of elements in the set.
(maths) the property of possessing a cardinal number
(maths, logic) (of a class) the cardinal number associated with the given class. Two classes have the same cardinality if they can be put in one-to-one correspondence
1520s, “condition of being a cardinal,” from cardinal (n.) + -ity. Mathematical sense is from 1935 (see cardinal (adj.)).
The number of elements in a set. If two sets have the same number of elements (i.e. there is a bijection between them) then they have the same cardinality. A cardinality is thus an isomorphism class in the category of sets.
aleph 0 is defined as the cardinality of the first infinite ordinal, omega (the number of natural numbers).
of prime importance; chief; principal: of cardinal significance. of the color cardinal. Roman Catholic Church. a high ecclesiastic appointed by the pope to the College of Cardinals and ranking above every other ecclesiastic but the pope. Also called cardinal grosbeak. a crested grosbeak, Cardinalis cardinalis, of North America, the male of which is bright red. […]
the process in which fibers, as cotton, worsted, or wool, are manipulated into sliver form prior to spinning. a usually rectangular piece of stiff paper, thin pasteboard, or plastic for various uses, as to write information on or printed as a means of identifying the holder: a 3″ × 5″ file card; a membership card. […]
card2 (defs 1, 2). Historical Examples The carding-machine is gone, and has given place to a rustic cider-press. Pastoral Days William Hamilton Gibson Doffer, dof′ėr, n. the part of a carding-machine which strips the cotton from the cylinder when carded. Chambers’s Twentieth Century Dictionary (part 1 of 4: A-D) Various When it is cleaned, it […]
a combining form meaning “heart,” used in the formation of compound words: cardiogram. Contemporary Examples This is a nice way to shake up the routine and will really add an element of cardio the exercise. Squats: The Absolutely Incredible Secret to Staying in Shape Ari Meisel January 1, 2014 Those carbs need to be burned […]