noun
first bath of the year
Refers to the first bath taken in the new year, often with special significance or ritual. Compare 初湯 (はつゆ), which can also mean the first bath of the year but may be used in the context of public baths or hot springs.
See also: 初湯
元旦に初風呂に入るのが我が家の習慣です。
It's our family custom to take the first bath of the year on New Year's Day.