conspiratorial

From conspiratory.

• IPA^(key): /kənˌspɪɹəˈtɔːɹɪəl/

conspiratorial (comparative more conspiratorial, superlative most conspiratorial)

1. Pertaining to conspiracy or conspirators.

   His conspiratorial whispers were soft, but that just attracted more attention.

   • 1960, P[elham] G[renville] Wodehouse, chapter X, in Jeeves in the Offing, London: Herbert Jenkins, →OCLC:

     I pressed the button and he appeared, giving me, as he entered, the sort of conspiratorial glance the acting secretary of a secret society would have given a friend on the membership roll. “Oh, Swordfish,” I said, having given him a conspiratorial glance in return, for one always likes to do the civil thing, “this is Mr Herring, who has come to join our little group.”

2. (sometimes proscribed) Believing in conspiracy theories.
   • 2021 April 29, Sabrina Tavernise, “Vaccine Skepticism Was Viewed as a Knowledge Problem. It’s Actually About Gut Beliefs.”, in The New York Times‎, New York, N.Y.: The New York Times Company, →ISSN, →OCLC, archived from the original on 2021-04-29:

     Conspiratorial thinking is another predictor of vaccine hesitancy, according to the 2018 study.

• conspiratory

• conspiracy
• conspirator
• conspiratorily

• “conspiratorial”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.