IMPULSIVE
hotheaded, impulsive, impetuous, madcap, tearaway, brainish
(adjective) characterized by undue haste and lack of thought or deliberation; âa hotheaded decisionâ; âliable to such impulsive acts as hugging strangersâ; âan impetuous display of spending and gamblingâ; âmadcap escapadesâ; (âbrainishâ is archaic)
capricious, impulsive, whimsical
(adjective) determined by chance or impulse or whim rather than by necessity or reason; âa capricious refusalâ; âauthoritarian rulers are frequently capriciousâ; âthe victim of whimsical persecutionsâ
driving, impulsive
(adjective) having the power of driving or impelling; âa driving personal ambitionâ; âthe driving force was his innate enthusiasmâ; âan impulsive forceâ
impulsive
(adjective) without forethought; âletting him borrow her car was an impulsive act that she immediately regrettedâ
impulsive, unprompted
(adjective) proceeding from natural feeling or impulse without external stimulus; âan impulsive gesture of affectionâ
Source: WordNet® 3.1
Etymology
Adjective
impulsive (comparative more impulsive, superlative most impulsive)
Having the power of driving or impelling; giving an impulse; moving; impellent.
Actuated by impulse or by transient feelings; inclined to make rapid decisions without due consideration.
(mechanics) Acting momentarily, or by impulse; not continuous â said of forces.
Noun
impulsive (plural impulsives)
That which impels or gives an impulse; an impelling agent.
One whose behaviour or personality is characterized by being impulsive.
Source: Wiktionary
Im*pul"sive, a. Etym: [Cf. F. impulsif.]
1. Having the power of driving or impelling; giving an impulse;
moving; impellent.
Poor men! poor papers! We and they Do some impulsive force obey.
Prior.
2. Actuated by impulse or by transient feelings.
My heart, impulsive and wayward. Longfellow.
3. (Mech.)
Definition: Acting momentarily, or by impulse; not continuous; -- said of
forces.
Im*pul"sive, n.
Definition: That which impels or gives an impulse; an impelling agent. Sir
W. Wotton.
Source: Webster’s Unabridged Dictionary 1913 Edition