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.
Weston said that anyone who fancies "throwing themselves headfirst down a mountain" should take the opportunity.
From BBC • Feb. 16, 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
On each project, she bears a new side to herself, often diving headfirst into the depths of her identity, love life and womanhood.
From Los Angeles Times • Nov. 14, 2025
His helmet-wearing partner appeared to be in such a hurry that he dived headfirst onto the platform, police said.
From The Wall Street Journal • Oct. 31, 2025
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 "The Undead Fox of Deadwood Forest" by Aubrey Hartman
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.
