# locus

In genetics, the locus is the position on a chromosome where a specific gene is located.

In mathematics, a locus is the set of all points (usually forming a curve or surface)
that satisfy some condition. For example, the locus of points in the
plane equidistant from a given point is a circle. Plural is 'loci.'
The Latin word *locus* simply means place.' (The Greek equivalent
is *topos*, which crops up in 'topology.')