The boundary-line of that part of the earth's surface visible from a given point of view; the line at which the earth and sky appear to meet. In…

= horizon, n. Obsolete.

The furthest visible edge of the sea, a range of hills, etc.; the horizon. Also figurative: the uttermost limit of knowledge, experience, etc.

clear sky near a dark horizon; also, the horizon.

The line at which the earth or a part of the landscape appears to meet the sky; the horizon. Also: a representation of this in a painting…

the line where sky and sea seem to meet: in Navigation, ‘the small circle which bounds the portion of the surface visible to a spectator in the…

poetic. The horizon.

The horizon, the line where sea and sky seem to meet.

The sea horizon.