Absence; the state of a person or thing not being present in the expected place.
部長は現在不在です。戻り次第ご連絡します。
The manager is currently absent. I'll contact you as soon as he returns.
不在通知がポストに入っていた。
A delivery notice was left in the mailbox.
会議中に彼の不在が目立った。
His absence was noticeable during the meeting.
Used as a suffix meaning disregard or the absence of an expected party (e.g., 国民不在: 'absence of the public'); often critical or evaluative.
国民不在の政治は信頼を失う。
Politics without the people's involvement loses trust.
議論が専門家不在で進められたのは問題だ。
It's problematic that the discussion proceeded without experts.