- a particular position, point, or place；the effective or perceived location of something abstract
noun: locus, plural noun: loci
- 1. technical a particular position, point, or place it is impossible to specify the exact locus in the brain of these neural events
- ▪ the effective or perceived location of something abstract the real locus of power is the informal council
- ▪ the position of a gene or mutation on a chromosome.
- 2. a curve or other figure formed by all the points satisfying a particular equation of the relation between coordinates, or by a point, line, or surface moving according to mathematically defined conditions a parabola is the locus of a point that moves so as to be equidistant from a fixed point and a straight line