triangulation pillar

English

Noun

triangulation pillar (plural triangulation pillars)

1. (UK) A concrete pillar used by the Ordnance Survey as a point for taking theodolite measurements, used in determining the exact shape of the country in a mid-20th-century retriangulation project.

Synonyms

• triangulation station
• trigpoint
• trig pillar
• trigonometrical station

Further reading

• triangulation pillar on Wikipedia.Wikipedia