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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

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.

A part of him—indeed, a large part—was enjoying this charade, this moment wherein he plunged headfirst into this caricature the humans had created.

From Literature

Rounding a corner, I almost ran headfirst into two cadets.

From Literature

As he reached the frozen shore, he lunged forward headfirst, his belly making slippery contact with the flat, smooth ice.

From Literature

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

From BBC

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

From BBC

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.