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

These figures are necessarily conjectural, because your mileage may vary — in fact, everyone’s mileage varies.

From Los Angeles Times • Dec. 10, 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

I find it bizarre to suggest that the plaintiffs have a “close relationship” with this totally conjectural class of patients.

From Slate • Apr. 12, 2023

All relied on the weight disparity between isotopes 235 and 238, but all were experimental, and their potential for industrial-scale production conjectural.

From "Big Science" by Michael Hiltzik