perpendicular

Short definition from Wiktionary

Adjective

1. 1
   At or forming a right angle (to something).
2. 2
   Exactly upright; extending in a straight line toward the centre of the earth, etc.
3. 3
   Independent of or irrelevant to each other; orthogonal.
4. 4
   Of a style of English Gothic architecture from the fourteenth and fifteenth centuries, marked by stiff and rectilinear lines, mostly vertical window-tracery, depressed or four-centre arch, fan-tracery vaulting, and panelled walls.

Noun

1. 1
   A line or plane that is perpendicular to another.
2. 2
   A device such as a plumb line that is used in making or marking a perpendicular line.
3. 3
   A meal eaten at a tavern bar while standing up.