in·sou·ci·ant (ĭn-ssē-ənt, ăɴ′s-syäɴ)
Marked by blithe unconcern; nonchalant.
[French : in-, not (from Old French; see IN-1) + souciant, present participle of soucier, to trouble (from Old French, from Vulgar Latin *sollicītāre, alteration of Latin sollicitāre, to vex; see SOLICIT).]
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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.