noun
first year of an era; inaugural year of a reign era
Used in Japanese era dating for the first year of an imperial era name; e.g. 令和元年 means the first year of Reiwa, not 令和一年 in formal date style.
令和元年に結婚しました。
We got married in the first year of Reiwa.
平成元年は1989年です。
The first year of Heisei is 1989.
noun
first year of a new development; year when something began
Figurative use for the year an important trend, industry, technology, or movement is considered to have started; common in media-style phrases like AI元年.
2024年は生成AI元年と呼ばれることがある。
2024 is sometimes called the first year of generative AI.
その大会は、女子サッカー人気の元年になった。
That tournament became the starting year for the popularity of women's soccer.