horizontally; flat
Describes something lying flat or oriented horizontally, often in contrast to vertical (縦に).
本を横に置いてください。
Please place the book horizontally.
彼は疲れてベッドに横になった。
He was tired and lay down flat on the bed.
Used for movement or orientation that is lateral, across, or to the side, often implying a direction perpendicular to the main axis.
車が横に並んで駐車している。
The cars are parked side by side.
He moved sideways to make way.
Adverbial form of the noun 横 (side), with the particle に indicating direction or state.