1 a : fraudulently substituted : spurious
b : (of a child) falsely presented as a genuine heir : illegitimate
2 a : imaginary
"… James II's queen, Mary of Modena, gave birth to a son and heir, the future Old Pretender, whom William's supporters tried to discredit as a supposititious child, smuggled in via a warming-pan." — Keith Thomas, The Guardian, 5 Apr. 2008
"I sat looking at Peggotty for some time, in a reverie on this supposititious case: whether, if she were employed to lose me like the boy in the fairy tale, I should be able to track my way home again by the buttons she would shed." — Charles Dickens, David Copperfield, 1850
Did You Know?
The Latin verb supponere, meaning "substitute," has several legitimate heirs in English, including supposititious (which dates from the early 17th century) and supposition (a 15th-century addition). The "fraudulent" and "illegitimate" meanings of supposititious trace back to supponere in a fairly direct route, whereas the "imaginary" and "hypothetical" meanings were influenced by the meanings of supposition. In legal contexts, supposititious is primarily used in its earlier senses, as in "a supposititious (fraudulent) will" or "the child was supposititious (illegitimate)." When something hypothetical is being considered, the synonymous adjective suppositious is often preferred over supposititious.
Test Your Vocabulary with M-W Quizzes
Test Your Vocabulary
Fill in the blanks to complete a noun that can refer to a supposition or to a conclusion drawn by guesswork: _ _ n _ e_ t _ re.VIEW THE ANSWER
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