'conjecture' originates from Latin, specifically the word 'coniectura', where 'con-' meant 'together' and 'iacere' meant 'to throw'.

'coniectura' transformed into the Old French word 'conjecture', and eventually became the modern English word 'conjecture'.

Initially, it meant 'interpretation or inference', but over time it evolved into its current meaning of 'an opinion or conclusion formed on the basis of incomplete information'.