locus

noun

lo·​cus ˈlō-kəs How to pronounce locus (audio)
plural loci ˈlō-ˌsī How to pronounce locus (audio)
-ˌkī,
-ˌkē
1
a
: the place where something is situated or occurs : site, location
was the culture of medicine in the beginning dispersed from a single focus or did it arise in several loci?S. C. Harvey
b
: a center of activity, attention, or concentration
in democracy the locus of power is in the peopleH. G. Rickover
2
: the set of all points whose location is determined by stated conditions
3
: the position in a chromosome of a particular gene or allele

Examples of locus in a Sentence

The area became a locus of resistance to the government. an area of the Southwest that has been the locus of a number of New Agey movements
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This approach uncovered 408 genetic loci (regions on the genome) associated with frailty – 371 of these had never before been linked to aging. New Atlas, 21 Aug. 2025 Washington’s deadlock has created a tectonic shift transferring power — and the locus for activity — back to the regions. Russell Hancock, Mercury News, 16 Aug. 2025 So whether the browser will be the locus of our agentic AI future or not is yet to be determined. John Koetsier, Forbes.com, 16 Aug. 2025 This makes the administration seem like a particularly untrustworthy locus for a registry to track autistic people. Thomas G. Moukawsher, MSNBC Newsweek, 24 Apr. 2025 See All Example Sentences for locus

Word History

Etymology

Latin — more at stall

First Known Use

1648, in the meaning defined at sense 1a

Time Traveler
The first known use of locus was in 1648

Cite this Entry

“Locus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/locus. Accessed 29 Aug. 2025.

Kids Definition

locus

noun
lo·​cus ˈlō-kəs How to pronounce locus (audio)
plural loci ˈlō-ˌsī How to pronounce locus (audio)
-ˌkī,
-ˌkē
1
2
: the set of all points whose location is determined by stated conditions
3
: the position in a chromosome of a particular gene or allele

Medical Definition

locus

noun
lo·​cus ˈlō-kəs How to pronounce locus (audio)
plural loci
ˈlō-ˌsī, -ˌkī also -ˌkē
1
: a place or site of an event, activity, or thing
the integrity of the tissues determines the extent and locus of the damageSylvia E. Hines
2
: the position in a chromosome of a particular gene or allele

Legal Definition

locus

noun
lo·​cus ˈlō-kəs How to pronounce locus (audio)
: the place connected with a particular event having legal significance

More from Merriam-Webster on locus

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