The definition of impetus is the force that makes something happen or that makes a body move.(noun)
If someone calls you stupid and this prompts you to go back to college, this comment was an example of theimpetus you needed to go back to college.
See impetus in Webster's New World College Dictionary
noun pl. impetuses
Origin: L < impetere, to rush upon < in-, in + petere, to rush at: see feather
See impetus in American Heritage Dictionary 4
noun pl. im·pe·tus·es
Origin: Middle English impetous
Origin: , from Latin impetus
Origin: , from impetere, to attack
Origin: : in-, against; see in-2
Origin: + petere, to go towards, seek; see pet- in Indo-European roots.
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