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im·plac·a·ble

(ĭm-plăkə-bəl, -plākə-)

adj.

Impossible to placate or appease: implacable foes; implacable suspicion.

[Middle English, from Old French, from Latin implācābilis : in-, not; see IN-¹ + plācābilis, placable; see PLACABLE.]

im·plac′a·bili·ty n.

im·placa·bly adv.

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:

Indo-European Roots

Semitic Roots

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.

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