Fathom

A legacy unit of depth equal to six feet (1.8288 m).

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Related F-terms

Fore

Forward, or toward the bow.

Fast

Secured — held in place, tied off.

Forestay

Standing rigging running from the bow (or stemhead) up to the mast, to which the foresail …

Fire extinguisher

A portable pressure-charged bottle used to fight fire on board; yachts typically carry Cla…

Fractional rig

A rig in which the forestay meets the mast below the masthead (e.g. 7/8 or 9/10 of mast he…

Full

A sail drawing properly, filled with wind and not luffing.

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