Standard Lemma guide
Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.
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noun
Any of several techniques used to measure the age of rock, especially any technique of radiometric dating, the measuring of the relative abundance of particular radioactive or radiogenic isotopes in order to evaluate the progress of radioactive decay.
Definition source: English Wiktionary via Wiktextract
Topics: geography, geology, natural-sciences
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
noun
Any of several crystalline minerals that remain stable over geologic time and that when formed contained radioisotopes whose abundance relative to their decay products can be measured to calculate the age of the crystal (and thus that of the surrounding rock).
Definition source: English Wiktionary via Wiktextract
No example sentence was provided for this meaning.
Synonyms: none provided
Antonyms: none provided
History
Etymology tree Pre-Greek der. Proto-Hellenic *gayader. Ancient Greek γαῖᾰ (gaîă)clip. Ancient Greek γῆ (gê) Ancient Greek -ο- (-o-) Ancient Greek γεω- (geō-)der. English geo- English chronometer English geochronometer From geo- + chronometer.
Across languages
1 source translations are retained for this English entry.
