The Collaborative International Dictionary of English v.0.48:

Standard \Stand"ard\ (-[~e]rd), n. [OF. estendart, F.
   ['e]tendard, probably fr. L. extendere to spread out, extend,
   but influenced by E. stand. See Extend.]
   1. A flag; colors; a banner; especially, a national or other
      ensign.
      [1913 Webster]

            His armies, in the following day,
            On those fair plains their standards proud display.
                                                  --Fairfax.
      [1913 Webster]

   2. That which is established by authority as a rule for the
      measure of quantity, extent, value, or quality; esp., the
      original specimen weight or measure sanctioned by
      government, as the standard pound, gallon, or yard.
      [1913 Webster]

   3. That which is established as a rule or model by authority,
      custom, or general consent; criterion; test.
      [1913 Webster]

            The court, which used to be the standard of
            propriety and correctness of speech.  --Swift.
      [1913 Webster]

            A disposition to preserve, and an ability to
            improve, taken together, would be my standard of a
            statesman.                            --Burke.
      [1913 Webster]

   4. (Coinage) The proportion of weights of fine metal and
      alloy established by authority.
      [1913 Webster]

            By the present standard of the coinage, sixty-two
            shillings is coined out of one pound weight of
            silver.                               --Arbuthnot.
      [1913 Webster]

   5. (Hort.) A tree of natural size supported by its own stem,
      and not dwarfed by grafting on the stock of a smaller
      species nor trained upon a wall or trellis.
      [1913 Webster]

            In France part of their gardens is laid out for
            flowers, others for fruits; some standards, some
            against walls.                        --Sir W.
                                                  Temple.
      [1913 Webster]

   6. (Bot.) The upper petal or banner of a papilionaceous
      corolla.
      [1913 Webster]

   7. (Mech. & Carp.) An upright support, as one of the poles of
      a scaffold; any upright in framing.
      [1913 Webster]

   8. (Shipbuilding) An inverted knee timber placed upon the
      deck instead of beneath it, with its vertical branch
      turned upward from that which lies horizontally.
      [1913 Webster]

   9. The sheth of a plow.
      [1913 Webster]

   10. A large drinking cup. --Greene.
       [1913 Webster]

   Standard bearer, an officer of an army, company, or troop,
      who bears a standard; -- commonly called color sergeantor
      color bearer; hence, the leader of any organization; as,
      the standard bearer of a political party.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

30 Moby Thesaurus words for "standard bearer":
   Mahdi, bell cow, bell mare, bellwether, born leader, boss, cacique,
   charismatic leader, choirmaster, choragus, conductor, coryphaeus,
   duce, file leader, forerunner, fugleman, inspired leader, keynoter,
   leader, leader of men, man higher up, messiah, pacemaker,
   pacesetter, policy maker, precentor, ringleader, sachem,
   symphonic conductor, torchbearer