Past tense of conjecture; guessed or inferred something without complete evidence. As an adjective: believed or guessed but not proven.
From Latin coniectura. The past tense marker -ed in English comes from Old English and originally signified a separate action before becoming a simple past marker.
Every brilliant scientific theory started as something 'conjectured'—Newton conjectured gravity from observing an apple, and it took generations to prove he was right.
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