A horizon

noun

ˈā-

: the uppermost dark-colored layer of a soil consisting largely of partly disintegrated organic debris

Word History

First Known Use

1896, in the meaning defined above

Time Traveler

The first known use of A horizon was in 1896

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Style

“A horizon.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/A%20horizon. Accessed 31 Oct. 2025.

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Kids Definition

A horizon

noun

A ho·ri·zon

ˈā-hə-ˌrī-zən

: the outer dark-colored soil with a light texture consisting usually of soil rich in debris obtained from living things in various stages of disintegration

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A horizon

noun

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