Finger (unit)

Some hand-based measurements, including the finger.

A chart of Imperial and US customary units.

A finger (sometimes fingerbreadth or finger's breadth) is any of several units of measurement that are approximately the width of an adult human finger. [Exactly which part of the finger should be used is not defined; the width at the base of fingernail (#6 in the sketch) is typically less than that at the knuckle (#5).]

The digit, also known as digitus or digitus transversus (Latin), dactyl (Greek) or dactylus, or finger's breadth –3⁄4 of an inch or 1⁄16 of a foot. ^{[1] [2]} (about 2 cm)

In medicine and related disciplines (anatomy, radiology, etc.) the fingerbreadth (literally the width of a finger) is an informal but widely used unit of measure. ^{[3] [4]}

In the measurement of distilled spirits, a finger of whiskey refers to the amount of whiskey that would fill a glass to the level of one finger wrapped around the glass at the bottom. ^{[5] [6] [7]}

Another definition (from Noah Webster): "nearly an inch." ^{[8] [9]}

Finger is also the name of a longer unit of length, used historically in cloth measurement, to mean one eighth of a yard or 4⁠1/2⁠ inches. ^{[8] [10]} (114.3 mm) Again, which finger and whose finger, is not defined.

These units have no legal status but remain in use for 'rough and ready' comparisons.

See also

• Digit (unit) ('6' in the diagram above)
• Finger tip unit  – Unit of ointment dosage in Medicine
• English units  – System of units formerly used in England (before 1826)
• Imperial units  – System of measurements (from 1826)
• United States customary units  – Units of measurement commonly used in the U.S.

References

1. Noah Webster; John Walker (1830). American dictionary of the English language. digit: Converse. p.  247 . Retrieved 15 January 2012.
2. Ronald Edward Zupko (1985). A dictionary of weights and measures for the British Isles: the Middle Ages to the twentieth century. American Philosophical Society. pp.  109–10. ISBN   978-0-87169-168-2.
3. The American Journal of the Medical Sciences. Charles B. Slack. 1839. p.  363 . Retrieved 15 January 2012.
4. David V. Skinner (28 April 1997). Cambridge textbook of accident and emergency medicine. Cambridge University Press. p. 1209. ISBN   978-0-521-43379-2 . Retrieved 15 January 2012.
5. University chronicle. 1858. p. 187. Retrieved 15 January 2012.
6. Bret Harte (1899). "A Jack and Jill of the Sierras". McClure's magazine. S.S. McClure Co. p. 230.
7. Harvard Student Agencies, Inc. The official Harvard Student Agencies bartending course. Macmillan. p.  38. ISBN   978-0-312-25286-1.
8. Noah Webster (1896). Webster's collegiate dictionary. G. & C. Merriam. p. 332. Retrieved 14 January 2012.
9. William Markham (1739). A general introduction to trade and business: or, The young merchant's and tradesman's magazine ... A. Bettesworth and C. Hitch. p.  104.
10. The Encyclopedia Americana. Encyclopedia Americana Corp. 1920. p.  165.