Definitions
1.verbTo copulate, as bucks and does.
2.verbTo bend; buckle.
3.verb(of a horse or similar saddle or pack animal) To leap upward arching its back, coming down with head low and forelegs stiff, forcefully kicking its hind legs upward, often in an attempt to dislodge or throw a rider or pack.
4.verb(of a horse or similar saddle or pack animal) To throw (a rider or pack) by bucking.
5.verbTo subject to a mode of punishment which consists of tying the wrists together, passing the arms over the bent knees, and putting a stick across the arms and in the angle formed by the knees.
6.verb(by extension) To resist obstinately; oppose or object strongly."The vice president bucked at the board's latest solution."
7.verb(by extension) To move or operate in a sharp, jerking, or uneven manner."The motor bucked and sputtered before dying completely."
8.verb(by extension) To overcome or shed (e.g., an impediment or expectation), in pursuit of a goal; to force a way through despite (an obstacle); to resist or proceed against."John is really bucking the odds on that risky business venture. He's doing quite well."
9.verb(riveting) To press a reinforcing device (bucking bar) against (the force of a rivet) in order to absorb vibration and increase expansion. See Wikipedia: Rivet:Installation.
10.verbTo saw a felled tree into shorter lengths, as for firewood.
11.verbTo output a voltage that is lower than the input voltage. See Wikipedia: Buck converter
12.verbTo soak, steep or boil in lye or suds, as part of the bleaching process.
13.verbTo wash (clothes) in lye or suds, or, in later usage, by beating them on stones in running water.
14.verbTo break up or pulverize, as ores.