See headlong in Webster's New World Roget's A-Z Thesaurus II
adjective
Characterized by unthinking boldness and haste:
brash, foolhardy, harum-scarum, hasty, hotheaded, ill-considered, impetuous, improvident, impulsive, incautious, madcap, precipitant, precipitate, rash1, reckless, slapdash, temerarious, unconsidered. See careful
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