Not being what it purports to be; false, fake, or based on false reasoning or information.
From Latin 'spurius' meaning 'illegitimate, false', possibly related to 'spernere' (to reject or despise). The word originally described illegitimate children, then broadened to mean anything not genuine or authentic.
Spurious originally described children born outside of marriage, carrying heavy social stigma about legitimacy. The word's evolution from describing people to describing false arguments shows how concepts of authenticity have shifted from bloodlines to evidence.
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