Singular

Singular. Not general; being in one place at one time.

(1) Applicable, as a sign, to a single individual.

(2) In mathematics: a singular place upon a continuum is a place whose properties differ from those of all other places in the vicinity, so as to constitute in one aspect a discontinuity.

If a sign refers to an object well known already to utterer and interpreter, and gives neither party any latitude as to what it represents, it may be called a singular sign, or singular.

If a sign allows no latitude, either to utterer or to interpreter, as t what object or meaning it shall be regarded as representing, it may be called a singular sign.

…a sign cannot be at once vague and general in the same respect. It may, however, be both definite and individual; and in that case may be said to be used singularly. ‘Man’ is used vaguely in ‘Some man sins’; generally, in ‘Every man sins’; singularly, in ‘This man sins.’