also: あくび
noun
unlucky day; bad day
Refers to a day considered inauspicious or unlucky, often in the context of traditional calendars or fortune-telling.
今日は悪日だから、大事なことはしないほうがいい。
Today is an unlucky day, so it's better not to do anything important.
Compound of 悪 (bad) and 日 (day). The reading あくにち is the standard on'yomi combination, while あくび is a less common variant.