the branch of lexicostatistics that studies the rate of replacement of vocabulary and attempts to determine what percentage of basic vocabulary two presently distinct but related languages share, using the information thus obtained to estimate how long ago they ceased being a single language.
Origin of glottochronology
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
the use of lexicostatistics to establish that languages are historically related
Word Origin for glottochronology
C20 glotto-, from Greek glōtta tongue
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