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Synonyms

headlong

American  
[hed-lawng, -long] / ˈhɛdˌlɔŋ, -ˌlɒŋ /

adverb

  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.


adjective

  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.

headlong British  
/ ˈhɛdˌlɒŋ /

adverb

  1. with the head foremost; headfirst

  2. with great haste

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

adjective

  1. archaic (of slopes, etc) very steep; precipitous

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of headlong

First recorded in 1350–1400; Middle English hedlong, earlier hedling; see head, -ling 2

Explanation

Headlong describes something done headfirst, rashly, or really quickly. If you’re the star batter on your baseball team, it’s expected that you'll make a headlong dive for the base. Headlong can refer to hasty actions, but it can also be used more figuratively to describe decisions that are reckless or made in a hurry. Your sister may tend to weigh all the options, but you make headlong decisions. When you decided headlong to move to Florida for a chance to play professionally, your sister thought you’d gone off your rocker — but the day you sign a major contract, she’ll be singing a different tune.

Keep Reading on Vocabulary.com

Vocabulary lists containing headlong

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Some argue a headlong commercial race will inevitably incentivize companies to cut corners on safety.

From The Wall Street Journal Jun. 5, 2026

But the race to deploy AI agents is running headlong into a scramble for the chips and energy needed to power them.

From Barron's May 6, 2026

“It looks like they’re running headlong into a brick wall,” Valatsas said.

From The Wall Street Journal Jan. 21, 2026

It’s fun, headlong reading with a shot of melancholy.

From Los Angeles Times Jan. 20, 2026

Ordinarily Mack would have thrown himself headlong into this problem but now he was not to be deflected.

From "Cannery Row" by John Steinbeck

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