Fathom

Fathom (Greek orguia, from a verb meaning "to stretch") was a unit of nautical depth measurement equal to six feet — the span of a man's outstretched arms. The term appears once in the New Testament, in the account of Paul's shipwreck, when the sailors sounded the depth of the sea and found "twenty fathoms" (approximately 120 feet), and shortly after "fifteen fathoms" (Acts 27:28), the shallowing confirming their approach to land in darkness.

The old English word "fathom" derives from the Anglo-Saxon faethm ("bosom" or the outstretched arms), paralleling the Greek etymology. As a nautical measurement, the fathom remained standard practice for centuries. The detail in Acts 27 reflects Luke's accurate depiction of first-century seamanship and contributes to the recognized historical precision of his account of Paul's voyage to Rome.