開館（かいかん、kaiかn）
- opening (of building)

The Japanese word 開館 (かいかん) means "opening of a facility" or "to open a building/institution (to the public)." It refers to the act of starting the operation of a public building, museum, library, or similar establishment. The term emphasizes the beginning of its service to the public. The term often implies setting hours of operation and making the facility accessible to visitors. It can also describe the state of being open for business or public access.

⚫︎ 博物館は9時に開館します。 Translation: The museum opens at 9 o'clock. ⚫︎ 図書館の開館時間は午前10時から午後6時までです。 Translation: The library's opening hours are from 10 am to 6 pm. ⚫︎ 新しい美術館が来月開館する予定です。 Translation: The new art museum is scheduled to open next month.

⚫︎ 開館 is commonly used in announcements, schedules, and informational materials related to public facilities. ⚫︎ It is appropriate to use it when talking about the starting time of operation or the date a building begins to be accessible to the public. ⚫︎ You can use it when asking about operating hours or describing when a building is open.

⚫︎ The word is typically written with the kanji 開 (かい, meaning "to open") and 館 (かん, meaning "building" or "hall"). ⚫︎ The hiragana reading is かいかん. ⚫︎ There are no significant variations in okurigana. ⚫︎ 開館 itself is a noun.

⚫︎ オープン (ōpun): This is a loanword from English "open" and is sometimes used interchangeably, especially in more casual contexts. However, 開館 is generally preferred for official announcements. ⚫︎ 開設 (かいせつ): This means "establishment" or "opening," often referring to the beginning of a service or operation.

⚫︎ 閉館 (へいかん): This means "closing of a facility" or "to close a building."

美術館の開館時間は火曜日から日曜日の午前10時から午後5時までです。 ・Translation: The museum's opening hours are from 10 am to 5 pm, Tuesday through Sunday. ・Explanation: This sentence provides the specific operating hours of the art museum.

新しい科学館が来年4月に開館するそうです。 ・Translation: I hear that the new science museum will open next April. ・Explanation: This sentence announces the scheduled opening of a new science museum.

The word 開館 is formed by combining the kanji 開 (kai), which means "to open" or "to start," with 館 (kan), which means "building," "hall," or "institution." Together, the characters represent the act of opening a building or facility to the public.