# geometric mean

## noun

: the nth root of the product of n numbers
specifically : a number that is the second term of three consecutive terms of a geometric progression
the geometric mean of 9 and 4 is 6

## Examples of geometric mean in a Sentence

Recent Examples on the Web That meant that the geometric mean titers of BA.4/BA.5 antibodies were 5.11-fold higher for those who received the new booster compared to those who received a booster of the original Moderna Covid vaccine if those people had been previously infected with Covid. Matthew Herper, STAT, 14 Nov. 2022 And would that be the arithmetic mean, or the geometric mean? Sean Carroll, Discover Magazine, 3 May 2010 There are actually three other kinds of mean: the geometric mean, the weighted mean, and the harmonic mean. Avery Hurt, Discover Magazine, 16 Sep. 2021 Compared with pre-booster antibody levels, the geometric mean fold rise in BA.4/5 antibodies rose 6.3-fold among mRNA-1273.214 recipients but only 3.5-fold for recipients of the current booster. Beth Mole, Ars Technica, 11 July 2022 By one measure, known as the geometric mean ratio (GMR), the monovalent 30 microgram booster compared to the current booster was 2.23; the 60 microgram monovalent booster had a GMR of 3.15 (higher is better). Matthew Herper, STAT, 28 June 2022 Before the fourth booster, all the seronegative participants had geometric mean titers (GMT) of omicron neutralizing antibodies at around 300. Beth Mole, Ars Technica, 8 June 2022 In the case of omicron, the combo shot generated neutralizing antibody levels twice as high as the current shot (when comparing geometric mean titres). Beth Mole, Ars Technica, 21 Apr. 2022 In the study, participants had neutralizing antibodies, measured in a unit called a geometric mean titer, of 224 to 354, on day 29 after their first vaccine dose; those levels reached 288 to 488 by day 57. Matthew Herper, STAT, 13 Jan. 2021

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'geometric mean.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

## Word History

First Known Use

1879, in the meaning defined above

Time Traveler
The first known use of geometric mean was in 1879

geometric mean

## Cite this Entry

“Geometric mean.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/geometric%20mean. Accessed 20 Jun. 2024.

## More from Merriam-Webster on geometric mean

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