In a way that is intended for or understood by only a small group of people with specialized knowledge.
From 'esoteric' + '-ally' (adverbial suffix). Standard English adverb formation where the adjective takes the '-ly' suffix to modify verbs or other adjectives.
When philosophers write esoterically, they're not always trying to be annoying—sometimes complex ideas genuinely require specialized terminology, though some scholars definitely use obscure language to sound more impressive than they actually are.
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