1. parallel to the ground or horizon; flat and level
2. relating to or involving people or things at the same level in a hierarchy
Usage: business

1. a horizontal line, plane, or position

Examples

• The table has a horizontal surface.
• Draw a horizontal line across the page.
• The building has horizontal stripes painted on it.
• The company encourages horizontal communication between departments.
• She adjusted the picture until it was perfectly horizontal.
• The horizon creates a natural horizontal in the landscape.
• The gymnast performed on the horizontal bar.