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im·pos·si·ble

(ĭm-pŏsə-bəl)

adj.

1. Incapable of having existence or of occurring.

2. Not capable of being accomplished: an impossible goal.

3. Unacceptable; intolerable: impossible behavior.

4. Extremely difficult to deal with or tolerate: an impossible child; an impossible situation.

[Middle English, from Old French, from Latin impossibilis : in-, not; see IN-¹ + possibilis, possible; see POSSIBLE.]

im·possi·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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