In a spiteful, malicious, or hateful manner.
Adverbial form of the archaic adjective dispiteous, created by adding -ly in the manner of 17th-century English word formation.
Many archaic adverbs ending in -ously sound genuinely menacing compared to their modern counterparts—there's something about the long, hissing 's' sounds that made old writers reach for words like this when they wanted to convey real venom.
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