A traditional unit of measurement in seafaring, strictly equal to six feet or exactly 1.8288 meters. It is used extensively on nautical charts to indicate soundings, and by deck crews to measure out anchor chain or heavy towing hawsers. While many international charts have transitioned to metric depths, the fathom remains standard in US waters and in traditional seamanship terminology.
Heard on the job
We're anchoring in ten fathoms, so pay out at least three shackles of chain.
Insider tip
When pulling up a line hand-over-hand, a full arm span from an adult's left hand to their right hand is roughly one fathom.