Jacob's staff

American  

noun

Jacob's staves plural

1. Astronomy. cross-staff.

2. Surveying. a pole providing a firm support for a compass or other instrument.

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Jacob's staff British  

noun

1. a medieval instrument for measuring heights and distances

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Other Word Forms

Noun Inflected Forms

• Jacob's staves
  plural

Etymology

Origin of Jacob's staff

First recorded in 1540–50

Example Sentences

A third instrument, also to measure the height of a celestial body, was called the Jacob's staff.

From The Age of the Reformation by Smith, Preserved

By Jacob's staff, I swear I have no mind of feasting forth to-night; But I will go.

From The Merchant of Venice by Shakespeare, William

The instrument is mounted on a tripod or Jacob's staff by means of a socket on the underside.

From Early American Scientific Instruments and Their Makers by Bedini, Silvio A.

Also, the name of the geometrical cross called Jacob's staff.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

A vainglorious knight, over-Englishing his travels, and wholly consecrated to singularity; the very Jacob's staff of compliment; a sir that hath lived to see the revolution of time in most of his apparel.

From Character Writings of the 17th Century by Various