unimaginably
adverb/ˌʌnɪˈmædʒɪnəbli/
/ˌʌnɪˈmædʒɪnəbli/
(formal)- in a way that is impossible to imagine
- Distances between the stars are unimaginably vast.
Check pronunciation:
unimaginably
Definition of unimaginably adverb from the Oxford Advanced Learner's Dictionary