Widthwise refers to something that is oriented or measured parallelly along the width or across the width of an object or space. Synonyms for widthwise include crosswise, sidewise, athwart, horizontally, and perpendicular. Crosswise and sidewise both denote something oriented perpendicular to the length, while the term athwart implies something placed at an angle across the width. Horizontally is an adjective used to refer to something aligned parallel to the horizon, while perpendicular refers to something that is at an angle of 90 degrees to a given plane or line. Other related synonyms for widthwise include breadthwise, transversely, and diagonally.