soliton: (physics) a quantum of energy or quasiparticle that can be propagated as a traveling wave in nonlinear systems and is neither preceded nor followed by another such disturbance; does not obey the superposition principle and does not dissipate
traveling wave: a wave in which the medium moves in the direction of propagation of the wave
genus crotalaria: large genus of herbs with simple leaves and racemes of yellow flowers; mainly of tropical Africa