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ir·ri·tate

(ĭrĭ-tāt′)

v. ir·ri·tat·ed, ir·ri·tat·ing, ir·ri·tates

v.tr.

1. To cause (someone) to feel impatient or angry; annoy: a loud, bossy voice that irritates listeners. See Synonyms at annoy.

2. To make sore or inflamed: The smoke irritated my eyes.

3. Physiology To cause a physiological response to a stimulus in (a cell, body tissue, or organism).

v.intr.

To be a cause of impatience or anger.

[Latin irrītāre, irrītāt-.]

irri·tat′ing·ly adv.

irri·ta′tor n.

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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