Unknown
Unidentified
noun, な adjective, の adjective
Something is not detailed at all. I don't know anything about it. No details whatsoever. It's a totally unknown entity. It's unidentified.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
昨日、年れい不詳な美人女性に出会ったんだ。
Yesterday, I met a beautiful woman of unknown age.
ワニカニは、性別不詳のモンスターです。
Wanikani is a monster whose sex is unknown.
彼ってほんと職業不詳だよね。
His real job is unknown, isn’t it?