conjectural

American  

[kuhn-jek-cher-uhl] / kənˈdʒɛk tʃər əl /

adjective

1. of, of the nature of, or involving conjecture; problematical.

   Theories about the extinction of dinosaurs are highly conjectural.

   Synonyms:

   doubtful, theoretical, speculative

2. given to making conjectures.

   a conjectural thinker.

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conjectural British  

/ kənˈdʒɛktʃərəl /

adjective

1. involving or inclined to conjecture

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Other Word Forms

• conjecturally adverb
• unconjectural adjective

Etymology

Origin of conjectural

1545–55; < Latin conjectūrālis, equivalent to conjectūr ( a ) conjecture + -ālis -al ¹

Example Sentences

Projections of economic gains from major sporting events are typically optimistic, euphoric, chimerical or conjectural.

From Los Angeles Times • Jun. 19, 2025

"It's a conjectural but plausible evolutionary theory - one that can't be proven, but makes sense," says Anoop Misra, who heads Delhi's Fortis-C-DOC Centre of Excellence for Diabetes, Metabolic Diseases and Endocrinology.

From BBC • Apr. 12, 2025

Without confirmation from artists, their teams, or Braun himself, changes to Braun’s roster are conjectural.

From Seattle Times • Aug. 23, 2023

Although these hazards are so far entirely conjectural, they are undoubtedly driving a growing community of researchers to study various harm-reduction tactics.

From Scientific American • Apr. 4, 2023

Conant had advised Bush to put the uranium project on the shelf for the duration of the war, but that advice had been based on his impression that a bomb was purely conjectural.

From "Big Science" by Michael Hiltzik