Out-of-bounds — synonyms, definition

1. out-of-bounds (Adjective)

off-limits

out-of-bounds (Adjective) — Outside the foul lines.

out-of-bounds (Adjective) — Barred to a designated group. ex. "that area is out-of-bounds"

2. out-of-bounds (Noun)

sideline

out-of-bounds (Noun) — A line that marks the side boundary of a playing field.

line touchline