Fathom

This article is about the unit of length. For other uses, see Fathom (disambiguation).
fathom
Standard units in Regensburg: the metal rods are (from left to right) a fathom (klafter), foot (schuch, Modern German Schuh "shoe") and ell (öln, Modern German Elle).
General information
Unit systemimperial/US units
Unit oflength
Conversions
1 fathom in ...... is equal to ...
   imperial/US units   6 ft
   SI unit equivalent   1.8288 m

A fathom is a unit of length in the imperial and the U.S. customary systems equal to 6 feet (1.8288 m), used especially for measuring the depth of water.[1] The fathom is neither an international standard (SI) unit, nor an internationally accepted non-SI unit. Historically it was the maritime measure of depth in the English-speaking world but, apart from within the US, charts now use metres.

There are two yards (6 feet) in an imperial fathom.[1] Originally the span of a man's outstretched arms, the size of a fathom has varied slightly depending on whether it was defined as a thousandth of an (Admiralty) nautical mile or as a multiple of the imperial yard. Formerly, the term was used for any of several units of length varying around 5–5+1⁄2 feet (1.5–1.7 m).

  1. ^ a b Chisholm, Hugh, ed. (1911). "Fathom" . Encyclopædia Britannica. Vol. 10 (11th ed.). Cambridge University Press. p. 201.