Definition of Jacob's staff in English:

Jacob's staff

Syllabification: Ja·cob's staff

noun

A rod with a sliding cursor formerly used for measuring distances and heights, especially in navigation.
More example sentences
  • In January 1472 he made observations of a comet, using his Jacob's staff, which were accurate enough to allow it to be identified with Halley's comet 210 years (and three returns of the 70 year period comet) later.

Origin

mid 16th century (denoting a pilgrim's staff): alluding to St. James (Jacobus in ecclesiastical Latin), whose symbols are a pilgrim's staff and a scallop shell.

Definition of Jacob's staff in:

Get more from Oxford Dictionaries

Subscribe to remove ads and access premium resources

Word of the day hypnopompic
Pronunciation: ˌhipnəˈpämpik
adjective
relating to the state immediately preceding waking up...