Casually unconcerned or indifferent. See Synonyms at cool.
[French, from Old French, present participle of nonchaloir, to be unconcerned : non-, non- + chaloir, to cause concern to (from Latin calēre, to be warm, heat up; see kelə-1 in the Appendix of Indo-European roots).]
non′cha·lance (-läns) n.
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.