impulsive

Etymology

It is inherited from Middle English impulsif,^[2][3] borrowed from Medieval Latin impulsīvus,^[2][4][3][5] from impulsus (“driven onwards”), the past participle of impellō (“to strike against, push against”), with the suffix -ive.^[2][6][4] The OED, Merriam-Webster and Klein also allow a borrowing of Middle French impulsif, recorded in French from the 14th century.^[4][7][6][8] The Latin verb is formed from in- (“into, against”) and pellō (“to push, drive”), which Watkins traces to Proto-Indo-European *pel- (“to thrust, strike, drive”).^[2] Merriam-Webster derives the French word from impulsion with the suffix -if.^[7]

Earliest recorded meaning

Of a medicine, one that reduces swellings or humours: early 15th century, as impulsif.^[2] Dictionary.com dates this earlier sense to 1375–1425,^[3] and the Oxford Dictionary of English gives the late Middle English sense as "tending to impel".^[8] The OED's first quotation, for impelling or determining to action, is from Harpsfield's treatise on the divorce of Henry VIII, before 1575.^[4]

Semantic evolution

In the 16th and 17th centuries the word was used of forces and causes: an impulsive cause was an originating or primary cause, a phrase frequent in the 17th century and now rare.^[4] From 1604 it meant having the power of impelling or giving motion.^[4][2] Johnson (1755) defined it as having the power of impulse, moving, impellent.^[9] A noun, an impelling agent or cause, was used from before 1628 to 1659.^[4] In dynamics it was used from 1803 of a force acting for a very short time.^[4][10] From 1920 it was used of electrical impulses.^[4] The sense now most common, of people apt to act on sudden impulse, is recorded from 1847, in Leigh Hunt,^[4][2] and Etymonline takes it from impulse;^[2] the Oxford Dictionary of English dates it to the mid-18th century.^[8]

Timeline

• early 15th century – impulsif, of a medicine that reduces swellings.^[2]
• before 1575 – impelling to action, also in the phrase impulsive cause, a primary cause.^[4]
• 1604 – having the property of impelling; characterized by impetus.^[4][2]
• before 1628 – noun, an impelling agent or cause (obsolete by 1659).^[4]
• 1803 – in dynamics, of a force acting for a very short time.^[4]
• 1847 – of people, apt to act on sudden impulse.^[4][2]
• 1920 – consisting of electrical impulses.^[4]

Meanings

Adjective

1. Inclined to act on sudden whims or urges rather than careful thought: an impulsive young driver.^[10][7][4]
2. Done on impulse rather than planned; spontaneous: an impulsive decision to quit.^[10][7]
3. Having the power to drive or impel: an impulsive force.^[10][7][4]
4. In physics, of a force, acting for a very short time; not continuous.^[10][4]

Word family

• impulsively
• impulsiveness
• impulsivity
• nonimpulsive
• unimpulsive

Related words

• impulse
• impulsion
• impel
• compulsive
• repulsive
• propulsive
• pulse

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
3. ^ a b c Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
4. ^ a b c d e f g h i j k l m n o p q r s Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
5. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
6. ^ a b Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
7. ^ a b c d e Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
8. ^ a b c Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
9. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.
10. ^ a b c d e Collins English Dictionary (2023), Glasgow: HarperCollins