1. [n]  the act of restraining power or action or limiting excess; "his common sense is a bridle to his quick temper"
2. [n]  a stock exchange in New York
3. [n]  an edge between a sidewalk and a roadway consisting of a line of curbstones (usually forming part of a gutter)
4. [n]  a horse's bit with an attached chain or strap to check the horse
5. [v]  place restrictions on; "curtail drinking in school"
6. [v]  to put down by force or authority; "suppress a nascent uprising"; "stamp down on littering"; "conquer one's desires"
7. [v]  keep to the curb; "curb your dogs"
8. [v]  lessen the intensity of; temper; hold in restraint; hold or keep within limits; "moderate your alcohol intake"; "hold your tongue"; "hold your temper"; "control your anger"

Curb
Curb

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1. \Curb\ (k?rb), v. t. [imp. & p. p. {Curbed} (k?rbd); p. pr.
   & vb. n. {Curbing}.] [F. courber to bend, curve, L. curvare,
   fr. curvus bent, curved; cf. Gr. ?????? curved. Cf. {Curve}.]
   1. To bend or curve [Obs.]
            Crooked and curbed lines.             --Holland.
   2. To guide and manage, or restrain, as with a curb; to bend
      to one's will; to subject; to subdue; to restrain; to
      confine; to keep in check.
            Part wield their arms, part curb the foaming steed.
                                                  --Milton.
            Where pinching want must curbthy warm desires.
                                                  --Prior.
   3. To furnish wich a curb, as a well; also, to restrain by a
      curb, as a bank of earth.
   

2. \Curb\, v. i.
   To bend; to crouch; to cringe. [Obs.]
         Virtue itself of vice must pardon beg, Yea, curb and
         woo for leave to do him good.            --Shak.
   

3. \Curb\, n.
   1. That which curbs, restrains, or subdues; a check or
      hindrance; esp., a chain or strap attached to the upper
      part of the branches of a bit, and capable of being drawn
      tightly against the lower jaw of the horse.
            He that before ran in the pastures wild Felt the
            stiff curb control his angry jaws.    --Drayton.
            By these men, religion,that should be The curb, is
            made the spur of tyranny.             --Denham.
   2. (Arch.) An assemblage of three or more pieces of timber,
      or a metal member, forming a frame around an opening, and
      serving to maintain the integrity of that opening; also, a
      ring of stone serving a similar purpose, as at the eye of
      a dome.
   3. A frame or wall round the mouth of a well; also, a frame
      within a well to prevent the earth caving in.
   4. A curbstone.
   5. (Far.) A swelling on the back part of the hind leg of a
      horse, just behind the lowest part of the hock joint,
      generally causing lameness. --James Law.
   {Curb bit}, a stiff bit having branches by which a leverage
      is obtained upon the jaws of horse. --Knight.
   {Curb pins} (Horology), the pins on the regulator which
      restrain the hairspring.
   {Curb plate} (Arch.), a plate serving the purpose of a curb.
   {Deck curb}. See under {Deck}.