OXFORD DICTIONARY
locus, n. (pl. loci)
1 a position or point, esp. in a text, treatise, etc.
2 Math. a curve etc. 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.
3 Biol. the position of a gene, mutation, etc. on a chromosome.
L, = place
THESAURUS
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