Archaic adjective meaning full of malice, contempt, or spiteful intent; contemptuous.
From despite + -ous (suffix from Latin -osus meaning 'full of'). This archaic form competes with despiteful as an older English adjective formation.
English had several ways to say 'full of contempt'—despitous, despiteful, despiteous—and they all eventually collapsed into just a couple of modern words.
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