curb 
(kûrb)
(kûrb)n.
1. A concrete border or row of joined stones forming part of a gutter along the edge of a street.
2. An enclosing framework, such as that around a skylight.
3. A raised margin along an edge used to confine or strengthen.
4. Something that checks or restrains: High interest rates put a curb on spending.
5. A chain or strap that passes under a horse's lower jaw and serves in conjunction with the bit to restrain the horse.
6. A market, originally on a street or sidewalk, for trading securities that are not listed on a stock exchange.
tr.v. curbed, curb·ing, curbs
1.
a. To check, restrain, or control (an impulse or activity, for example); rein in. See Synonyms at restrain.
b. To prevent (a person or group) from doing something or acting in a certain way.
2. To lead (a dog) off the sidewalk into the gutter so that it can excrete waste.
3. To furnish with a curb.
[Blend of Middle English, curved piece of wood (from Old French corbe, curved object, from corbe, curved, from Latin curvus) and Middle English corbe, horse strap (from corben, to bow down, halt, from Old French corber, to bow down, from Latin curvāre, from curvus, curved, bent; see sker-2 in the Appendix of Indo-European roots).]