a. Careful forethought to avoid danger or harm.
b. Close attention or vigilance to minimize risk: The car proceeded over the rickety bridge with caution.
2. Prudence or restraint in action or decision: advised caution in choosing a school.
3. A warning or admonishment, especially to take heed: I received a caution from the doctor about fat in my diet.
4. A cautious action; a precaution: The climbers took the necessary cautions in preparing for the ascent.
5. Informal One that is striking or alarming.
v. cau·tioned, cau·tion·ing, cau·tions
To warn or admonish: cautioned him not to go swimming alone; cautioned that the findings were not conclusive.
To give a warning or admonishment: cautioned against overeating.
[Middle English caucioun, from Old French caution, from Latin cautiō, cautiōn-, from cautus, past participle of cavēre, to take care.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.