loci

UK: /ˈləʊsaɪ/ US: (lō′sī, -kē, -kī)

From locus (n):

loci

npl

loca

npl

WordReference Random House Unabridged Dictionary of American English © 2026

lo•ci  (lō′sī, -kē, -kī), n. 

1. pl. of locus. 

Collins Concise English Dictionary © HarperCollins Publishers::

loci / ˈləʊsaɪ/ noun

1. the plural of locus

WordReference Random House Learner's Dictionary of American English © 2026

lo•cus /ˈloʊkəs/   n. [countable] , pl. -ci 

/-saɪ, -ki, -kaɪ/.  
1. a place;
   locality.
2. a center or source, as of activities or power:
   The locus of control is headquarters.

See -loc-.

WordReference Random House Unabridged Dictionary of American English © 2026

lo•cus  (lō′kəs), n., pl. -ci (-sī, -kē, -kī), -ca 

(-kə). 
1. a place;
   locality.
2. a center or source, as of activities or power:
   locus of control.
3. Mathematics the set of all points, lines, or surfaces that satisfy a given requirement.
4. Genetics the chromosomal position of a gene as determined by its linear order relative to the other genes on that chromosome.

• Latin; Old Latin stlocus a place
• 1525–35

Collins Concise English Dictionary © HarperCollins Publishers::

locus / ˈləʊkəs/ noun ( loci / ˈləʊsaɪ/)

1. (in many legal phrases) a place or area, esp the place where something occurred
2. a set of points whose location satisfies or is determined by one or more specified conditions: the locus of points equidistant from a given point is a circle
3. the position of a particular gene on a chromosome

Etymology: 18th Century: Latin