Length is a measure of distance. In the International System of Quantities, length is a quantity with dimension distance. In most systems of measurement a base unit for length is chosen, from which all other units are derived. In the International System of Units system the base unit for length is the metre. Length is commonly understood to mean the most extended dimension of a fixed object. However, this is not always the case and may depend on the position the object is in. Various terms for the length of a fixed object are used, and these include height, which is vertical length or vertical extent, and width, breadth or depth. Height is used when there is a base from which vertical measurements can be taken. Width or breadth usually refer to a shorter dimension when length is the longest one. Depth is used for the third dimension of a three dimensional object.

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Glassy gel is hard as plastic and stretches 7 times its length

Tiny Predator Astonishes With Neck That Stretches 30 Times Its Length

This protist unfolds its ‘neck’ up to 30 times its body length to scout prey

Explore full-length raw interviews for NOVA’s documentary “To the Moon" in the American Archive of Public Broadcasting!

The Future of Disease Detection: New Technology Identifies Individual Full-Length Human Proteins

Melting Polar Ice Is Having a Concerning Impact on The Length of Our Year

Climate change and polar ice melting could be impacting the length of Earth's day

New study finds 'sweet spot' for length of yarn-shaped supercapacitors

Study pinpoints the length of incidental activity linked to health benefits

Genetic evidence shows that smoking can cause us to age faster: study of 500,000 people has shown that smoking shortens the end fragments of chromosomes in the white blood cells. The length of these end fragments, is an indicator of how quickly we age

Evolution’s Whiplash: Plesiosaurs Doubled Their Neck-Length by Gaining New Vertebrae

Research shows that plesiosaurs doubled their neck length by gaining additional vertebrae.

Spring equinox 2023: Why day and night aren't actually equal in length

Motor abnormalities in people with depression: Recent research suggests depressed individuals have abnormal posture and sway, slow gait, decreased step/stride length and width, reduced number of steps to turn around, and reduced stepping reaction time.

Men’s penises are getting longer. Here’s why this is actually a problem | The average erect penis length has increased by nearly 25% in the last three decades.

Average pregnancy length in the US is shorter than in European countries

Length of REM Sleep Linked to Body Temperature

Magnetic sensors track muscle length

Magnesium ions slow down water dynamics on short length scales

Rewriting History – The First Full-Length Genomes for Homosporous Ferns