assuredly UK /əˈʃʊəɹɪdli/US /əˈʃʊɹɪdli/ adverb2 •In an assured manner; confidently.The hotel owner strode assuredly into the lobby. •For sure; certainly.I soon came to think that […] there was something, assuredly, very strange going on […] — 1973 formsmore assuredly · most assuredly