The word locus (plural loci) is Latin for "place":

• Locus (genetics), the position of a gene (or other significant sequence) on a chromosome.
• Locus (mathematics), the set of points satisfying a particular condition, often forming a curve of some sort.
• In the classics, literature or theology, locus (or locus classicus) marks the first appearance of a phrase or the definitive passage that is authoritative for an idea.

Locus may also refer to:

• Locus is also the title of a magazine carrying news about science fiction ^*.
• The method of loci is one of the major mnemonic systems.
• Locus is a racing computer game set in the future.

Locus | Locus | Locus | לוקוס (גנטיקה) | 遺伝子座