Length is a measurement of how long something is in time or space. You can measure the length of a table or the length of a movie.

If an object has multiple distances to be measured (like a rectangle for example), then length is taken to be the longest of the measurements (as opposed to the width, in the case of the rectangle). Before babies learn to walk, they are measured for length, but once they begin to stand reliably the same measurement changes names, and become height.

Definitions of length
  1. noun
    the linear extent in space from one end to the other; the longest dimension of something that is fixed in place
    “the length of the table was 5 feet”
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    the length of the closed curve of a circle
    diam, diameter
    the length of a straight line passing through the center of a circle and connecting two points on the circumference
    r, radius
    the length of a line segment between the center and circumference of a circle or sphere
    the property of being of long spatial extent
    the property of being of short spatial extent
    the apparent radius of a celestial body when viewed as a disc from the earth
    radius of curvature
    the radius of the circle of curvature; the absolute value of the reciprocal of the curvature of a curve at a given point
    bore, caliber, calibre, gauge
    diameter of a tube or gun barrel
    the space between the projectile of a smoothbore gun and the surface of the bore of the gun
    extension, lengthiness, prolongation
    amount or degree or range to which something extends
    the quality of being elongated
    type of:
    physical property
    any property used to characterize matter and energy and their interactions
    the magnitude of something in a particular direction (especially length or width or height)
    fundamental measure, fundamental quantity
    one of the four quantities that are the basis of systems of measurement
  2. noun
    size of the gap between two places
    “he determined the length of the shortest line segment joining the two points”
    synonyms: distance
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    (nautical) the distance traveled by a sailing vessel on a single tack
    arm's length
    a distance sufficient to exclude intimacy
    the distance between the rails of a railway or between the wheels of a train
    light time
    distance measured in terms of the speed of light (or radio waves)
    skip distance
    the shortest distance that permits radio signals (of a given frequency) to travel from the transmitter to the receiver by reflection from the ionosphere
    wingspan, wingspread
    linear distance between the extremities of an airfoil
    distance between the tips of the wings (as of a bird or insect) when fully extended
    the perpendicular distance from the base of a geometric figure to the opposite vertex (or side if parallel)
    broad gauge
    a railroad track (or its width) broader than the standard 56.5 inches
    narrow gauge
    a railroad track (or its width) narrower than the standard 56.5 inches
    standard gauge
    railroad track having the standard width of 56.5 inches
    type of:
    the physical magnitude of something (how big it is)
  3. noun
    a section of something that is long and narrow
    “a length of timber”
    “a length of tubing”
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    type of:
    section, segment
    one of several parts or pieces that fit with others to constitute a whole object
  4. noun
    continuance in time
    “he complained about the length of time required”
    synonyms: duration
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    duration as an extension
    continuation, lengthiness, prolongation, protraction
    the consequence of being lengthened in duration
    the property of being (or seeming to be) without end
    the property of being of short temporal extent
    brevity, briefness, transience
    the attribute of being brief or fleeting
    permanence, permanency
    the property of being able to exist for an indefinite duration
    impermanence, impermanency
    the property of not existing for indefinitely long durations
    length of service, longevity
    duration of service
    (music) a prolongation of unspecified length on a note or chord or rest
    ceaselessness, continuousness, incessancy, incessantness
    the quality of something that continues without end or interruption
    perpetuity, sempiternity
    the property of being perpetual (seemingly ceaseless)
    durability, enduringness, lastingness, strength
    permanence by virtue of the power to resist stress or force
    imperishability, imperishableness, imperishingness
    the property of being resistant to decay
    the property of being extremely durable
    the property of lasting only a short time
    transience, transiency, transitoriness
    an impermanence that suggests the inevitability of ending or dying
    the quality or state of being mortal
    the quality or state of being immortal
    the temporal property of being cut short
    the temporal property of being very short
    type of:
    temporal property
    a property relating to time
  5. noun
    the property of being the extent of something from beginning to end
    “the editor limited the length of my article to 500 words”
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    type of:
    the distance or area or volume over which something extends
Word Family

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