noun
standing room; standing-only seat
Refers to a ticket or area where you stand to watch a performance, sports event, etc., rather than having a seat.
コンサートの立ち見席はもう売り切れだ。
The standing-room tickets for the concert are already sold out.
立ち見席でも十分楽しめるよ。
You can still enjoy it even from the standing section.
Compound of 立ち見 (standing and watching) + 席 (seat/place). The meaning is transparent from its parts.