alidade: meaning, definition, pronunciation and examples
Rare / Very Low FrequencyTechnical, Scientific
Quick answer
What does “alidade” mean?
A sighting device or ruler used for determining directions or measuring angles in surveying, astronomy, and navigation.
Audio
Pronunciation
Definition
Meaning and Definition
A sighting device or ruler used for determining directions or measuring angles in surveying, astronomy, and navigation.
The part of a surveying or navigational instrument, such as a theodolite or plane table, consisting of a sight or telescope mounted on a straightedge for plotting direction lines.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or spelling. Pronunciation differences follow standard regional patterns for the vowel sounds.
Connotations
None beyond the technical meaning.
Frequency
Equally rare and specialized in both varieties. Its use is confined to professional fields like surveying, cartography, and historical astronomy.
Grammar
How to Use “alidade” in a Sentence
[The alidade] + [is/was] + [used/rotated/placed] + [on the table/toward a point][Surveyor] + [sighted/used] + [the alidade] + [to measure/draw a line]Vocabulary
Collocations
Usage
Meaning in Context
Business
Not used.
Academic
Used in specialized academic texts on surveying, archaeology (for site mapping), and the history of astronomy and navigation.
Everyday
Not used; would be unknown to most general speakers.
Technical
The primary domain. Found in technical manuals, surveying textbooks, and engineering specifications for mapping equipment.
Vocabulary
Synonyms of “alidade”
Watch out
Common Mistakes When Using “alidade”
- Mispronouncing as /əˈliː.deɪd/ or /ˈæl.iː.deɪd/.
- Using it as a general term for any ruler.
- Confusing it with an 'altimeter' (height) or 'azimuth' (angle).
FAQ
Frequently Asked Questions
No, it is a very rare and highly technical term used only in specific fields like surveying, cartography, and historical astronomy.
You should not, as it would be unfamiliar to most listeners. Use simpler terms like 'sighting device' or 'ruler' for a general audience, though they are not precise equivalents.
An alidade is often a component *part* of a theodolite or plane table—the sighting mechanism. A theodolite is the complete instrument for measuring horizontal and vertical angles.
It comes via French and Medieval Latin from the Arabic 'al-'iḍādah' meaning 'the revolving radius'.
A sighting device or ruler used for determining directions or measuring angles in surveying, astronomy, and navigation.
Alidade is usually technical, scientific in register.
Alidade: in British English it is pronounced /ˈæl.ɪ.deɪd/, and in American English it is pronounced /ˈæl.ə.deɪd/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Imagine an 'alien dad' ('alidade') using a special sighting ruler to map new planets.
Conceptual Metaphor
Not applicable; a concrete tool term.
Practice
Quiz
What is the primary function of an alidade?