Jacob's staff

American  

noun

plural

Jacob's staves

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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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

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

Jacob's staff I swear, I have no mind of feasting forth to-night: But I will go.—Go you before me, sirrah; Say, I will come.

From Shakespeare's play of the Merchant of Venice Arranged for Representation at the Princess's Theatre, with Historical and Explanatory Notes by Charles Kean, F.S.A. by Kean, Charles John

The bear again disappeared, taking the Jacob's staff, and appeared no more that night.

From Bears I Have Met—and Others by Kelly, Allen

It seems you would be a fine capricious, mathematically jealous coxcomb; take the height of your own horns with a Jacob's staff, afore they are up.

From The White Devil by Webster, John