incautious

American  

[in-kaw-shuhs] / ɪnˈkɔ ʃəs /

adjective

1. not cautious; careless; reckless; heedless.

   Synonyms:

   headstrong, hotheaded, brash, rash

---

incautious British  

/ ɪnˈkɔːʃəs /

adjective

1. not careful or cautious

---

Other Word Forms

• incautiously adverb
• incautiousness noun

Etymology

Origin of incautious

1695–1705; in- ³ + cautious; compare Latin incautus in same sense

Explanation

If you're incautious, you don't worry about problems that might come up — you're a little irresponsible. An incautious person might paddle off in a kayak without putting a life jacket on. Incautious behavior might include betting your whole paycheck on a poker game, bringing six stray dogs home, or lighting a bottle rocket and launching it from your hand. Incautious children are probably used to hearing adults telling them to be careful. Incautious is a combination of in-, "not" and cautious, "careful." It's derived from the Latin adjective incautus stemming from the noun cautionem, "caution, care, or foresight."

Example Sentences

Even the animals are distinctive—especially Kōkī, the pet parrot who acts like a Shakespearean fool, squawking incautious truths to Tongan authority.

From The Wall Street Journal • Oct. 8, 2025

Hon also didn’t think of the Kraffts as incautious.

From New York Times • Jul. 6, 2022

Where the other astronauts look upon Glenn as sanctimonious, he finds them incautious.

From Los Angeles Times • Oct. 8, 2020

And media training seems to have been another incautious palace economy.

From The Guardian • Nov. 16, 2019

Although he was rash, untutored in the ways of the backcountry, and incautious to the point of foolhardiness, he wasn’t incompetent—he wouldn’t have lasted 113 days if he were.

From "Into the Wild" by Jon Krakauer