light year
Preserved but no longer current.
This is a term used by scientists as a unit in measuring stellar distances. Light travels at the rate of 186,000 miles a second; a light year, or the distance travelled by light in a year, is, therefore, 5,876,068,880,000 miles.
Era: ca. 1898 (Victorian)
Sources & notes
Reproduced from Brewer’s Dictionary of Phrase and Fable (1898 edition, public domain; archive.org, retrieved 2026-07-31; OCR text, minor errors possible). Reflects the scholarship and attitudes of its era.
Common questions
What does “light year” mean?
This is a term used by scientists as a unit in measuring stellar distances. Light travels at the rate of 186,000 miles a second; a light year, or the distance travelled by light in a year, is, therefore, 5,876,068,880,000 miles.
Is “light year” formal or informal?
No register label has been reviewed yet — treat it as neutral and check the usage notes above.