1. 
[syn: venue, locale, locus]
2.  the specific site of a particular gene on its chromosome; 
3.  the set of all points or lines that satisfy or are determined by specific conditions; 
- Example: "the locus of points equidistant from a given point is a circle"
The Collaborative International Dictionary of English v.0.48:
Locus \Lo"cus\, n.; pl. Loci, & Loca. [L., place. Cf.
   Allow, Couch, Lieu, Local.]
   1. A place; a locality.
      [1913 Webster]
   2. (Math.) The line traced by a point which varies its
      position according to some determinate law; the surface
      described by a point or line that moves according to a
      given law.
      [1913 Webster]
   Plane locus, a locus that is a straight line, or a circle.
   Solid locus, a locus that is one of the conic sections.
      [1913 Webster]
WordNet (r) 3.0 (2006):
locus
    n 1: the scene of any event or action (especially the place of a
         meeting) [syn: venue, locale, locus]
    2: the specific site of a particular gene on its chromosome
    3: the set of all points or lines that satisfy or are determined
       by specific conditions; "the locus of points equidistant from
       a given point is a circle"
Moby Thesaurus II by Grady Ward, 1.0:
27 Moby Thesaurus words for "locus":
   abode, area, bearings, bench mark, district, emplacement, hole,
   latitude and longitude, lieu, locale, locality, location, pinpoint,
   place, placement, point, position, region, site, situation, situs,
   spot, station, stead, where, whereabout, whereabouts
The Free On-line Dictionary of Computing (30 December 2018):
Locus
   A distributed system project supporting transparent access to
   data through a network-wide file system.