plural loci
ˈlō-ˌsī 
-ˌkī,
-ˌkē
1
b
: a center of activity, attention, or concentration
In democracy the locus of power is in the people.—
H. G. Rickover
H. G. Rickover2
: 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
The feeling was unfamiliar, since my usual mental coordinates place me somewhere in the proximate future, a locus of anticipation and, all too often, unfocused worry.
—Michael Pollan, The Atlantic, 26 Jan. 2026
Instead of cutting or permanently altering DNA, STX-1150 essentially installs modifications and DNA methylation marks at the PCSK9 locus in liver cells, which silences gene expression in a way that can be reversed if needed.
—New Atlas, 25 Jan. 2026
This is different than an external locus of control which focuses on reacting to all the waves of change coming in at us.
—Heather V. MacArthur, Forbes.com, 18 Jan. 2026
But while the event itself is a locus for all sorts of annual events, the stakes were even higher this year, with the ceremony moving from the first weekend of the year to a weekend conveniently right before Oscars nomination voting opens.
—Marcus Jones, IndieWire, 12 Jan. 2026
See All Example Sentences for locus
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Michael Pollan, The Atlantic, 26 Jan. 2026
Instead of cutting or permanently altering DNA, STX-1150 essentially installs modifications and DNA methylation marks at the PCSK9 locus in liver cells, which silences gene expression in a way that can be reversed if needed.
—New Atlas, 25 Jan. 2026
This is different than an external locus of control which focuses on reacting to all the waves of change coming in at us.
—Heather V. MacArthur, Forbes.com, 18 Jan. 2026
But while the event itself is a locus for all sorts of annual events, the stakes were even higher this year, with the ceremony moving from the first weekend of the year to a weekend conveniently right before Oscars nomination voting opens.
—Marcus Jones, IndieWire, 12 Jan. 2026
See All Example Sentences for locus
Cite this Entry
“Locus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/locus. Accessed 1 Feb. 2026.
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Medical Definition
locus
noun
lo·cus
ˈlō-kəs
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 damage—Sylvia E. Hines
Sylvia E. Hines2
: the position in a chromosome of a particular gene or allele
Legal Definition
locus
noun
lo·cus
ˈlō-kəs
: the place connected with a particular event having legal significance
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