conjectural

UK: /kənˈdʒɛktʃərəl/ US: (kən jek′chər əl)

WordReference Random House Unabridged Dictionary of American English © 2025

con•jec•tur•al  (kən jek′chər əl), adj. 

1. of, of the nature of, or involving conjecture;
   problematical:
   Theories about the extinction of dinosaurs are highly conjectural.
2. given to making conjectures:
   a conjectural thinker.

• Latin conjectūrālis, equivalent. to conjectūr(a) conjecture + -ālis -al¹
• 1545–55

con•jec′tur•al•ly, adv. 
Synonyms

• 1. speculative, theoretical, doubtful.

Collins Concise English Dictionary © HarperCollins Publishers::

conjectural / kənˈdʒɛktʃərəl/ adjective

1. involving or inclined to conjecture

conˈjecturally adverb