1833, "dealing with one side only of a question or dispute," hence, "partial, unjust, unfair," from one + side (n.). Translating German ein-seitiger. Related: One-sidedly; one-sidedness.
one-of-a-kind
one-off
onerous
oneself
one-shot
one-sided
one-stop
one-time
one-upsmanship
one-way
ongoing
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