careful

American  

[kair-fuhl] / ˈkɛər fəl /

adjective

1. cautious in one's actions.

   Be careful when you cross the street.

   Synonyms:

   circumspect, chary, guarded, watchful

   Antonyms:

   careless, careless, careless, careless

2. taking pains in one's work; exact; thorough.

   a careful typist.

   Synonyms:

   scrupulous, meticulous

   Antonyms:

   careless, careless, careless, careless

3. (of things) done or performed with accuracy or caution.

   careful research.

   Synonyms:

   rigorous

   Antonyms:

   careless, careless, careless, careless

4. solicitously mindful (usually followed by of, about, orin ).

   careful of the rights of others;

   careful about one's behavior;

   careful in speech.

   Synonyms:

   regardful, heedful, attentive, solicitous, concerned, thoughtful

   Antonyms:

   careless, careless, careless, careless

5. Archaic.

   1. full of anxiety or care; troubled.

   2. causing or attended with anxiety.

      a careful day.

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careful British  

/ ˈkɛəfʊl /

adjective

1. cautious in attitude or action; prudent

2. painstaking in one's work; thorough

   he wrote very careful script

3. (usually postpositive; foll by of, in, or about) solicitous; protective

   careful of one's reputation

4. archaic full of care; anxious

5. mean or miserly

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Related Words

Careful, cautious, discreet, wary imply a watchful guarding against something. Careful implies guarding against mistakes, by paying strict and close attention to details, and, often, trying to use good judgment: He was careful to distinguish between them. Cautious implies a fear of some unfavorable situation and investigation before coming to conclusions: cautious about investments. Discreet implies being prudent in speech and action and being trustworthy as a confidant: discreet in manner, in keeping secrets. Wary implies a vigilant lookout for a danger suspected or feared: wary of polite strangers. See painstaking.

Other Word Forms

• carefully adverb
• carefulness noun
• quasi-careful adjective
• ultracareful adjective

Etymology

Origin of careful

First recorded before 1000; Middle English; Old English carful, cearful; care, -ful

Explanation

If you consider all consequences and do a task thoughtfully, take your time and watch what you are doing, you are being careful. Can you ever be too careful? If you're a stunt man, yes. If you're an accountant, no. Being cautious has always been wise, and the word careful has been an admonishment since before the Tenth Century. In Old English, the word cearful meant "mournful" or "full of care or concern," the second meaning not too far from our current definition, that of "using care." While we are often warned to be careful about things in our life, Ralph Waldo Emerson observed that "A man is usually more careful of his money than he is of his principles."

Example Sentences

Former Liverpool and England defender Stephen Warnock told BBC Radio 5 Live that Slot needed to be "careful" with the teenager but that he had "earned his right to play".

From BBC • Apr. 11, 2026

The most important thing for candidates is to “emphasize they have worked with AI tools and they have done it in a responsible and careful fashion,” he said.

From MarketWatch • Apr. 11, 2026

We also need to be careful of what we wish for.

From Salon • Apr. 10, 2026

Cavallari: I remember having to be very careful about what I said — but not careful enough because I didn’t think about editing.

From Los Angeles Times • Apr. 9, 2026

That he understood how important this was, being careful with Thor.

From "A Boy Called Bat" by Elana K. Arnold

Related Words

• accurate
• attentive
• choosy
• circumspect
• concerned
• conscientious
• deliberate
• discreet
• judicious
• leery
• meticulous
• mindful
• precise
• prudent
• rigorous
• scrupulous
• sober
• thorough
• thoughtful
• vigilant