A horizon

[ey huh-rahy-zuhn]

noun

Geology.

1. the topsoil in a soil profile.

A horizon

noun

1. the top layer of a soil profile, usually dark-coloured and containing humus and from which soluble salts may have been leached See B horizon C horizon

A horizon

1. In ABC soil, the uppermost, darkest zone that is rich in organic matter. The upper section of the A horizon usually contains humus along with plant and animal matter in varying stages of decay. The middle section usually contains a high concentration of quartz or other minerals that remain following the leaching away of clay, iron, and aluminum. The lower section is typically transitional in nature between the A horizon and the B horizon.

2. Also called zone of leaching

Word History and Origins

Origin of A horizon¹

First recorded in 1935–40

Example Sentences

"The only way to defeat the ideology is by creating and presenting to the Palestinian and the Israeli people a new horizon. A horizon of two states."

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A horizon you could ride to in five minutes.

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A horizon without a few hartebeests on it would seem to be lacking in completeness.

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A horizon of deep purple marked the afterglow of sunset and preceded a desert night of stars.

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