• noun a British Imperial system unit of length, also used in the US, equal to 25.4 millimetres or 2.54 centimetres or 1/12 of a foot.


  • A measure of length equal to 1/12 of a foot (2.54 centimeters).


  • (written as Inch)
    A unit of distance equal to exactly 2.54 centimeters, or 0.0254 meters. Its abbreviation is in.


  • noun a unit of linear measure corresponding to 2.54 centimetres


  • noun a measurement of length equalling 2.54cm

General Science

  • abbreviationin.

Origin & History of “inch”

Inch and ounce both mean etymologically ‘one twelfth’, but while this ancestral sense has largely been lost sight of in the case of ounce, for inch it remains in force. The words’ common ancestor is Latin uncia, a term for a ‘twelfth part’ derived from unus ‘one’. This was borrowed into prehistoric Germanic as *ungkja, but it has not survived in any other Germanic language but English.