American Heritage Dictionary
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Century Dictionary
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GNU Webster's 1913
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WordNet
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Elsewhere on the web
I am irritable, and out of temper.— The Picture of Dorian Gray
Her temper is more irritable, and Mr. Gordon Cumming says:--"She is more dangerous before she has been a mother; yet every vestige of tameness or docility vanishes when she is a mother, and she is then in a constant state of excitement, getting into the most violent fury if any one should attempt to touch her cubs."— Anecdotes of the Habits and Instinct of Animals
Privations had made him irritable, and he had to bite his lip to keep down a bitter answer.— A Desert Drama Being The Tragedy Of The "Korosko"
As this mortifying conviction came home to her bosom, she grew restless, irritable, and captious to excess; she watched all his motions with a self-tormenting jealousy; she fed her own disquiet by listening to the malicious informations of his enemies; and her heart at length becoming callous by repeated exasperations, she began to visit his delinquencies with an unrelenting sternness.— Memoirs of the Court of Queen Elizabeth
You know that he is irritable, and that when he has taken up a prejudice it is difficult to eradicate it.— Ronald Morton, or the Fire Ships A Story of the Last Naval War

American Heritage Dictionary (1)
Century Dictionary (1)
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