Added 9 October 2026 hypothesize /haɪˈpɒθ.ɪ.saɪz/ verb Categories: Mind & IdeasRare Words verb ! Definition from WordNet 3.1, Princeton University. Pronunciation from Wiktionary, via Kaikki.org. More about hypothesize at Wordnik → Where our words come from → To believe especially on uncertain or tentative grounds. Scientists supposed that large dinosaurs lived in swamps Related Words: conjecturesupposespeculatetheorizehypothecatetheoriseguessassumepresumepositpostulatesuggest Back to today's word