index fossil
(in-dex-fos-sil)
3 syllables
Definition
noun. A fossil that is useful for dating and correlating the strata in which it is found.
Example Sentence
Geologists often use an index fossil to identify the age of sedimentary rock layers.
More Example Sentences
The presence of an index fossil helped scientists determine the geological period of the rock formation.
Synonyms
guide fossil; marker fossil; zone fossil
Antonyms
living fossil; contemporary organism; recent species
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index fossil
