Locus \Lo"cus\, n.; pl. {Loci}, & {Loca}. [L., place. Cf.
{Allow}, {Couch}, {Lieu}, {Local}.]
1. A place; a locality.
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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.
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{Plane locus}, a locus that is a straight line, or a circle.
{Solid locus}, a locus that is one of the conic sections.
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