I. noun
Synonyms: stimulus , catalyst, goad, impetus, impulse, incentive, incitation, incitement, motivation, stimulant
Related Word: excitant; activation, actuation
Antonyms: checkrein, curb
II. verb
Synonyms: urge , egg (on), exhort, goad, prick, prod, prompt, propel, sic
Related Word: rowel; arouse, awaken, rally, rouse, stir; instigate; countenance, favor
Antonyms: curb