A sign, stamp, or mark
impressed, as by a seal.
Especially, the name of any person, written
with his own hand, employed to signify that the writing which precedes
accords with his wishes or intentions] a sign manual; an
autograph.
An outward mark by which
internal characteristics were supposed to be indicated.
A resemblance between the
external characters of a disease and those of some physical agent, for
instance, that existing between the red skin of scarlet fever and a
red cloth; -- supposed to indicate this agent in the treatment of the
disease.
The designation of the key
(when not C major, or its relative, A minor) by means of one or more
sharps or flats at the beginning of the staff, immediately after the
clef, affecting all notes of the same letter throughout the piece or
movement. Each minor key has the same signature as its relative
major.
A
letter or figure placed at the bottom of the first page of each sheet
of a book or pamphlet, as a direction to the binder in arranging and
folding the sheets.
That part of a prescription
which contains the directions to the patient. It is usually prefaced
by S or Sig. (an abbreviation for the Latin
signa, imperative of signare to sign or mark).
In celebration of Noah Webster's Birthday (October 16, 2009), we have prepared an updated website. 
