diastem

[ dahy-uh-stem ]
/ ˈdaɪ əˌstɛm /

noun Geology.

a minor hiatus in an orderly succession of sedimentary rocks.
Compare unconformity.

Origin of diastem

1850–55; < Greek diástēma interval; see diastema
Related formsdi·a·stem·ic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019