numeric
Formal or literary numeric 'one', often used in counting or in fixed expressions. In everyday counting, いち is more common.
See also: 一つ (ひとつ)
一、二、三と数える。
Count one, two, three.
一に努力、二に努力。
First, effort; second, effort.
noun
Used in the adverbial phrase 一に to mean 'solely' or 'entirely', often in formal or literary contexts. Appears in expressions like 一に~による (it all depends on...).
See also: 一に
成功は一に努力にかかっている。
Success depends entirely on effort.
結果は一に君の判断次第だ。
The outcome depends solely on your judgment.