spirit level

American  

noun

Surveying.

1. a device for determining true horizontal or vertical directions by the centering of a bubble in a slightly curved glass tube or tubes filled with alcohol or ether.

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spirit level British  

noun

1. a device for setting horizontal surfaces, consisting of an accurate block of material in which a sealed slightly curved tube partially filled with liquid is set so that the air bubble rests between two marks on the tube when the block is horizontal

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Etymology

Origin of spirit level

First recorded in 1760–70

Example Sentences

He may have lost his pencil, hammer, spirit level and saw every 30 seconds, but he knew what he was doing.

From The Guardian

No wonder he stood on the touchline with lips pursed in such a rigid horizontal line that they could double as a spirit level.

From The Guardian

For Miller, wellness is about “people reconnecting and being comfortable in their mind and spirit level. Before, people were distracting themselves through consumerism.”

From The Guardian

Traversing Alaska’s shattered coastline by barge and bush plane, he employs the field geologist’s tools — hammer, spirit level, compass, notepad and, to “read” the landscape, his eyes.

From Los Angeles Times

The system comprises several small canals in which tiny amounts of fluid act like spirit levels, responding to the body's motion.

From BBC