noun

• (uncountable) Equality; comparability of strength or intensity.
• Senses related to classification into two sets.
• (mathematics, countable) A set with the property of having all of its elements belonging to one of two disjoint subsets, especially a set of integers split in subsets of even and odd elements.
• (mathematics, countable) The classification of an element of a set with parity into one of the two sets.
• (computing) The count of one bits in a value, reduced to even or odd or zero or one.
• (physics, countable) Symmetry of interactions under spatial inversion.
• (games, countable) In reversi, the last move within a given sector of the board.
• Resemblance; analogy.
• (medicine, countable) The number of delivered pregnancies reaching viable gestational age, usually between 20-28 weeks
• (agriculture, countable) The number of times a sow has farrowed.