aslant

The adverb is derived from Middle English aslant, aslante (“at an angle, in a curve; from the side; (figurative) deviously”), from on slant (“at an angle, obliquely”), from on (“above and touching (something), on; at (a place or position); etc.”, preposition) (from Old English on, ultimately from Proto-Germanic *an (“on, upon; on to”), from Proto-Indo-European *h₂en- (“on, on to”)) + slant, slante (“incline, slant”, noun) (probably from Old Norse slent, from Proto-Germanic *slintaną (“to slide; to slip”)). By surface analysis, a- (prefix meaning ‘at; in; on’ denoting a condition, manner, or state) + slant.

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