horizontal

UK: ˌhɒrɪˈzɒntəl | US: ˌhɔːrɪˈzɑːntəl

Definition
  1. adj. parallel to the plane of the horizon; level

  2. adj. relating to or situated near the horizon

  3. n. a horizontal line, plane, or direction

Structure
horizon <boundary>tal <adjective suffix>
Etymology

The word "horizontal" derives from the Late Latin horizontem (nominative horizon), meaning "boundary" or "limit," originally from the Greek horizōn kyklos ("limiting circle"). The suffix "-tal" (from Latin -alis) forms adjectives meaning "pertaining to." Thus, "horizontal" literally means "pertaining to the horizon," reflecting its geometric sense of alignment parallel to the earth's apparent boundary.

Examples
  1. The artist drew a horizontal line across the canvas.

  2. Lay the board in a horizontal position for stability.

  3. The horizon appears perfectly horizontal at sea.

  4. Adjust the shelf to ensure it is completely horizontal.

  5. Horizontal stripes can make a room look wider.