"angry, inclined to wrath," 1707, from Late Latin iracundus, from ira "anger, wrath, rage, passion" (see ire (n.)). Related: Iracundulous (1765).
[T]he Severn is so mischievous and cholerick a river, and so often ruins the country with sudden inundations, since it rises in Wales, and consequently participates sometimes of the nature of that hasty, iracund people among whom 'tis born. [Thomas Browne, "Letters from the Dead to the Living," 1707]
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