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

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