The Collaborative International Dictionary of English v.0.48:

Label \La"bel\, v. t. [imp. & p. p. Labeled (l[=a]"b[e^]ld) or
   Labelled; p. pr. & vb. n. Labeling or Labelling.]
   1. To affix a label to; to mark with a name, etc.; as, to
      label a bottle or a package.
      [1913 Webster]

   2. To affix in or on a label. [R.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Label \La"bel\ (l[=a]"b[e^]l), n. [OF. label sort of ribbon or
   fringe, label in heraldry, F. lambeau shred, strip, rag; of
   uncertain origin; cf. L. labellum, dim. of labrum lip, edge,
   margin, G. lappen flap, patch, rag, tatter (cf. Lap of a
   dress), W. llab, llabed, label, flap, Gael. leab, leob,
   slice, shred, hanging lip.]
   1. A tassel. [Obs.] --Huloet. --Fuller.
      [1913 Webster]

   2. A slip of silk, paper, parchment, etc., affixed to
      anything, and indicating, usually by an inscription, the
      contents, ownership, destination, etc.; as, the label of a
      bottle or a package.
      [1913 Webster]

   3. A slip of ribbon, parchment, etc., attached to a document
      to hold the appended seal; also, the seal.
      [1913 Webster]

   4. A writing annexed by way of addition, as a codicil added
      to a will.
      [1913 Webster]

   5. (Her.) A barrulet, or, rarely, a bendlet, with pendants,
      or points, usually three, especially used as a mark of
      cadency to distinguish an eldest or only son while his
      father is still living.
      [1913 Webster]

   6. A brass rule with sights, formerly used, in connection
      with a circumferentor, to take altitudes. --Knight.
      [1913 Webster]

   7. (Gothic Arch.) The name now generally given to the
      projecting molding by the sides, and over the tops, of
      openings in medi[ae]val architecture. It always has a
      square form, as in the illustration. --Arch. Pub. Soc.
      [1913 Webster]

   8. In medi[ae]val art, the representation of a band or scroll
      containing an inscription. --Fairholt.
      [1913 Webster]

WordNet (r) 3.0 (2006):

label
    n 1: a brief description given for purposes of identification;
         "the label Modern is applied to many different kinds of
         architecture"
    2: trade name of a company that produces musical recordings;
       "the artists and repertoire department of a recording label
       is responsible for finding new talent" [syn: label,
       recording label]
    3: a radioactive isotope that is used in a compound in order to
       trace the mechanism of a chemical reaction
    4: an identifying or descriptive marker that is attached to an
       object
    v 1: assign a label to; designate with a label; "These students
         were labelled `learning disabled'"
    2: attach a tag or label to; "label these bottles" [syn: tag,
       label, mark]
    3: pronounce judgment on; "They labeled him unfit to work here"
       [syn: pronounce, label, judge]
    4: distinguish (as a compound or molecule) by introducing a
       labeled atom
    5: distinguish (an element or atom) by using a radioactive
       isotope or an isotope of unusual mass for tracing through
       chemical reactions

The Free On-line Dictionary of Computing (19 January 2023):

label

   1.  An identifier used to mark a position in a
   program so that it can be the destination of a goto
   statement.

   2.  The identifier assigned to a datagram for
   label switching.

   (2007-10-17)