sup·​pos·​i·​ti·​tious | \ sə-ˌpä-zə-ˈti-shəs How to pronounce supposititious (audio) \

Definition of supposititious

1a : fraudulently substituted : spurious

b of a child

(1) : falsely presented as a genuine heir
(2) : illegitimate

2 [ influenced in meaning by supposition ]

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

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Other Words from supposititious

supposititiously adverb

Synonyms & Antonyms for supposititious


baseborn, bastard, illegitimate, misbegotten, natural, spurious, unfathered



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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 adjective "suppositious" is often preferred over "supposititious."

Examples of supposititious in a Sentence

entered the world as the supposititious son of a housemaid

First Known Use of supposititious

1600, in the meaning defined at sense 1a

History and Etymology for supposititious

Latin suppositicius, from suppositus, past participle of supponere to substitute

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Time Traveler for supposititious

The first known use of supposititious was in 1600

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