Pivot (Fr. pivot; probably connected with It. pivolo, peg, pin, diminutive of piva, pipa, pipe), that on which something turns; specifically a metal pointed pin or short shaft in machinery, such as the end of an axle or spindle.
The term occurs frequently in combination with others, chiefly in technical usage, e.g "pivot-gearing," for a system of gearing in machinery which admits of the shifting of the axis of a driving wheel, so that the power may be communicated in various directions.
In linguistics, the syntactic pivot is the argument of the verb around which the sentence "revolves" — typically the one that the verb agrees with, the one that can be sometimes be omitted and assumed to remain the same as in previous sentences, etc. (in nominative-accusative languages, this is the argument we call "subject").
In mathematics, specifically linear algebra, a pivot is the first non-zero value of each row of a matrix after the matrix has been converted to row echelon form. The number of pivots in a matrix is equal to the rank of the matrix.
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