Pronunciation: (hed'lông", -long"), [key]
1. with the head foremost; headfirst: to plunge headlong into the water.
2. without delay; hastily: to plunge headlong into work.
3. without deliberation; rashly: to rush headlong into battle.
1. undertaken quickly and suddenly; made precipitately; hasty: a headlong flight.
2. rash; impetuous: a headlong denunciation.
3. done or going with the head foremost: a headlong dive into the pool.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.