Bound and Zero hour

Bound noun - A real or imaginary point beyond which a person or thing cannot go.

Zero hour and bound are semantically related. In some cases you can use "Zero hour" instead a noun "Bound".

Nearby Words: bounded, boundless, boundary, bounding, boundlessness

Zero hour noun - A time or state of affairs requiring prompt or decisive action.

Bound and zero hour are semantically related. Sometimes you can use "Bound" instead a noun phrase "Zero hour".