impulse

Synonyms: actuation appeal bent caprice catalyst desire disposition excitant extemporization fancy feeling flash goad hunch impellent impulsion incitation incitement inclination influence inspiration instinct itch lash lust mind motivation motive notion passion spontaneity spur thought urge vagary whim whimsy wish yen

Synonyms: augmentation beat bump catalyst drive force impetus impulsion lash momentum movement pressure propulsion pulsation pulse push rush shock shove stroke surge thrust vibration