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Synonyms

headfirst

American  
[hed-furst] / ˈhɛdˈfɜrst /

adverb

  1. with the head or heads in front or bent forward; headforemost.

    He dived headfirst into the sea.

  2. rashly; precipitately.


headfirst British  
/ ˈhɛdˈfɜːst /

adjective

  1. with the head foremost; headlong

    he fell headfirst

"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

adverb

  1. rashly or carelessly

"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

Etymology

Origin of headfirst

First recorded in 1820–30; head + first

Explanation

When you do something headfirst, your head leads the way. For example, a boy might show off by diving headfirst into a chilly lake. The adverb headfirst is useful for describing a dive or a movement that leads with the head. A stormy ocean might fling a swimmer headfirst onto the beach, or an unlucky skier could slide headfirst down a mountain. You can also use headfirst in a more figurative way, to describe something that's done impulsively, or in a foolishly hasty manner: "He plunged headfirst into this new relationship two days after breaking up with his girlfriend."

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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:

Dramatic video footage obtained by TMZ shows the boy falling headfirst down the ride’s 50-foot-tall waterfall just behind the flume that he had exited.

From Los Angeles Times Jun. 24, 2026

He has, however, run headfirst into significant obstacles, both from the public and key institutions that have curtailed his ambitions.

From BBC Feb. 24, 2026

Weston said that anyone who fancies "throwing themselves headfirst down a mountain" should take the opportunity.

From BBC Feb. 16, 2026

First, the Coens submerge us headfirst into the cold netherworld of a Minnesota winter, where criminals hope that a dusting of fresh, frosty powder will cover their tracks.

From Salon Feb. 7, 2026

Tally somersaulted in the air, turning headfirst for a few terrifying moments, her face passing low enough to spot a discarded bottle cap in the grass.

From "Uglies" by Scott Westerfeld

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