hith·er·to
adverb/ˌhɪðəˈtuː/
/ˌhɪðərˈtuː/
(formal)- until now; until the particular time you are talking about
迄今；直到某时 - a hitherto unknown species of moth
迄今仍属未知品种的蛾 - Her life hitherto had been devoid of adventure.
迄今为止，她的生活缺乏冒险。
Oxford Collocations DictionaryHitherto is used with these adjectives:- impossible
- neglected
- unheard-of
- …
- a hitherto unknown species of moth