In geometric measurements, length most commonly refers to the longest dimension of an object.
In certain contexts, the term "length" is reserved for a certain dimension of an object along which the length is measured. For example it is possible to cut a length of a wire which is shorter than wire thickness. Another example is FET transistors, in which the channel width may be larger than channel length.
Length may be distinguished from height, which is vertical extent, and width or breadth, which are the distance from side to side, measuring across the object at right angles to the length.
Length is a measure of one dimension, whereas area is a measure of two dimensions (length squared) and volume is a measure of three dimensions (length cubed). In most systems of measurement, the unit of length is a fundamental unit, from which other units are defined.
Famous quotes containing the word length:
“At length to hospital
This man was limited,
Where screens leant on the wall
And idle headphones hung.
Since he would soon be dead
They let his wife come along
And pour out tea, each day.”
—Philip Larkin (1922–1986)
“They raise their minds by brooding over and embellishing their sufferings, from one degree of fervid exaltation and dreary greatness to another, till at length they run amuck entirely, and whoever meets them would do well to run them thro’ the body.”
—Thomas Carlyle (1795–1881)
“An ... important antidote to American democracy is American gerontocracy. The positions of eminence and authority in Congress are allotted in accordance with length of service, regardless of quality. Superficial observers have long criticized the United States for making a fetish of youth. This is unfair. Uniquely among modern organs of public and private administration, its national legislature rewards senility.”
—John Kenneth Galbraith (b. 1908)