In a way that cannot be easily explained or understood; mysteriously or without clear reason.
From Latin 'in-' (not) + 'explicable' (from 'explicare': to unfold/explain). The adverb form adds '-ly' to the adjective, following standard English word formation.
The word 'inexplicably' captures the frustration of encountering something that resists explanation—the 'ex-' in 'explicable' means to unfold, so 'inexplicable' means information that refuses to unfold into clarity.
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