unavoidably; necessarily; inevitably
Formal, somewhat literary adverb meaning that something cannot be helped or is bound to happen. Often used in written language or formal speech.
That outcome was unavoidable, and no one can be blamed.
時代の変化にはよぎょうなく対応しなければならない。
We must inevitably adapt to the changes of the times.
Means 'inevitably' with a nuance of logical or natural consequence, less about external compulsion.
Kanji spelling; rare and literary. The word is almost always written in kana in modern Japanese.
Variant kanji spelling with okurigana なく instead of 無く; equally rare.
From 余業 (yogyō, 'other work; alternative') + 無く (naku, adverbial form of 無い 'not exist'). Literally 'without alternative', hence 'unavoidably'. The exact historical derivation is uncertain, but the kanji spelling reflects this composition.