What does ～日 mean?
～日 is a Japanese noun meaning “~ days” in English. It can also be translated as “day ~ of the month” depending on context. It is written as ～日 in kanji, ～にち in hiragana, and ～nichi in romaji. This word is part of JLPT N5 vocabulary.
Example sentences
十一日に出発します。
I'm leaving on the eleventh.
十四日間、旅行しました。
I travelled for fourteen days.