locus

IPA/ˈləʊkəs/
KK[lˈokəs]IPA/ˈləʊkəs/

locus — noun

  • locussingular
  • locaplural

1. a formal word for the place where a particular event, activity, or situation hap

1.nounB2
Definition

a formal word for the place where a particular event, activity, or situation happens, or the main topic that attracts attention in a discussion.

Example

The old market square became the locus of political protests during the summer.

the locus of + event (political protests)

For Karim, the family farm was the locus of all his childhood memories.

locus of + abstract noun (memories)

Common collocations
  • locus of power
  • locus of control
  • locus of activity
  • locus of attention
  • central locus
  • primary locus
  • main locus
Synonyms
  • location

    the most general neutral term for a place; less formal than locus

  • site

    emphasises a specific place where something is built or an event occurs

  • centre

    focuses on the middle point of a physical area or of attention

  • focus

    emphasises the main subject of attention in a discussion or situation

Grammar Patterns

the locus of [event/interest/activity]

a locus for [purpose]

Usage Note

More formal than place or location. Best used in academic writing, journalism, or analytical discussion rather than everyday conversation.

Common Mistakes

We met at a quiet locus near the river.
We met at a quiet spot near the river.
locus sounds unnatural in casual speech; use place, spot, or location instead.

2. in mathematics, a set of points or lines whose positions all satisfy a given rul

2.nounC1
Definition

in mathematics, a set of points or lines whose positions all satisfy a given rule or condition, often forming a curve or a shape.

Example

A circle is the locus of all points that lie at the same distance from a fixed centre.

locus of points + geometric condition

In geometry class, Kabir had to find the locus of a point moving in a parabola.

find the locus of [shape/curve]

Common collocations
  • locus of points
  • locus of a point
  • locus of a curve
  • geometric locus
  • define the locus
  • plot the locus
Synonyms
  • curve

    a visual representation of a locus; less precise mathematically

  • set of points

    a more general descriptive phrase; locus is the standard technical term

Grammar Patterns

the locus of points [that/which + condition]

Common Mistakes

The parabola is a locus of points.
A parabola is the locus of all points that satisfy x² = 4ay.
locus in mathematics is usually introduced with 'the' and followed by a specific condition.

3. the fixed address on a chromosome where a specific gene or DNA segment is locate

3.nounC1
Definition

the fixed address on a chromosome where a specific gene or DNA segment is located, and where genetic information can be found or inherited.

Example

Scientists identified the locus on chromosome 7 that is linked to the inherited disorder.

locus on [chromosome number] + associated with [condition]

Dr. Kwame pointed to the specific locus on chromosome 17 while explaining the BRCA1 test results to his patient.

locus on [chromosome] + medical explanation context

Common collocations
  • gene locus
  • locus on chromosome
  • locus for a trait
  • locus of a mutation
  • mapped locus
  • single locus
  • locus heterogeneity
Synonyms
  • site

    a less technical term for a position on a chromosome

  • location

    a general word for a place; locus is the standard genetics term

  • genetic marker

    a locus used as a reference point in mapping; not all loci are markers

Grammar Patterns

the locus for [gene]

locus on [chromosome number]

Usage Note

In genetics papers, locus is often abbreviated as 'loci' (plural). The plural ending is pronounced 'loh-sai' or 'loh-see'.

Common Mistakes

The locus of the gene was on chromosome 5.' (acceptable but vague).
The BRCA1 locus is located on chromosome 17 at position 17q21.
in genetics writing, a specific locus name is usually given rather than a general statement.

Word family

Synonym discussion

Sense: noun/1

Location is the most general and neutral term for a place, covering everything from a street address to a country; it is the best everyday substitute for 'locus'. Site emphasises a specific place selected for a purpose, such as a building site or a historic site. Venue is restricted to events — a concert hall, sports stadium, or conference centre. Focus shifts from physical place to the thing that draws the most attention, mental or otherwise. For example: 'The city was the location of the summit'; 'The factory site will be redeveloped'; 'The stadium is the venue for the final match'; 'The budget became the focus of the meeting.' Locus carries a more analytical or academic tone than any of these alternatives.

location ↗site ↗venue ↗focus ↗

Common collocations

Nouns

Adverbs

Phrases

  • locus of control
  • locus of power
  • locus of activity
  • locus of attention

Prepositions

Etymology

LatinEnglish

Directly borrowed from Latin locus, meaning 'place' or 'spot'. The word entered English in the early 15th century with the same general meaning. By the 18th century, mathematicians adopted it for the set of points satisfying a condition. In the early 20th century, geneticists used it to name the fixed position of a gene on a chromosome — an address, as it were, within the genome.