Word of the Day:

1 a : fraudulently substituted : spurious

b : (of a child) falsely presented as a genuine heir : illegitimate

2 a : imaginary

b : of the nature of or based on a supposition : hypothetical

"… 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

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.