adjective
adverb
Etymology
Origin of headfirst
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."
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.
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
Besides Kjellbin and Savolainen, newlyweds Kim Meylemans and Nicole Silveira are hurtling headfirst toward a marital showdown between Belgium and Brazil.
From The Wall Street Journal ● Feb. 13, 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
I have to, more or less, crawl into the barrel, headfirst.
From "Shine!" by J.J. and Chris Grabenstein
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.