al·​i·​dade | \ ˈa-lə-ˌdād How to pronounce alidade (audio) \

Definition of alidade

: a rule equipped with simple or telescopic sights and used for determination of direction: such as
a : a part of an astrolabe
b : a part of a surveying instrument consisting of the telescope and its attachments

Examples of alidade in a Sentence

Recent Examples on the Web Dalton showed the couple around the lookout, explaining the old telephone system and the fire finder, a type of alidade used by fire lookouts., "High in the Cascades, fire lookouts are still on the lookout for danger - The Boston Globe," 29 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alidade.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of alidade

15th century, in the meaning defined above

History and Etymology for alidade

Middle English allidatha, from Medieval Latin alhidada, from Arabic al-ʽiḍāda the revolving radius of a circle

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The first known use of alidade was in the 15th century

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Cite this Entry

“Alidade.” The Dictionary, Merriam-Webster Inc., Accessed 28 January 2020.

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Comments on alidade

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showing steady, earnest care and effort

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