noun, noun which may take the genitive case particle 'no'
Refers to the initial stage or starting point of a period, plan, or situation. Often used in formal or written contexts.
当初の計画では、来月完成する予定だった。
According to the original plan, it was supposed to be completed next month.
noun, adverb
at first; initially; originally
Adverbial use meaning 'in the beginning' or 'at the outset', often contrasting with a later change or outcome.
当初は反対だったが、今は賛成だ。
I was against it at first, but now I'm in favor.
当初、この問題は軽視されていた。
Initially, this problem was underestimated.