ORTHOG'RAPHY, noun [Gr. right, and writing.]

1. The art of writing words with the proper letters, according to common usage.

2. The part of grammar which treats of the nature and properties of letters, and of the art of writing words correctly.

3. The practice of spelling or writing words with the proper letters.

4. In geometry, the art of delineating the fore right plane or side of any object, and of expressing the elevations of each part; so called because it determines things by perpendicular lines falling on the geometrical plane.

5. In architecture, the elevation of a building, showing all the parts in their true proportion.

6. In perspective, the fore right side of any plane, that is, the side or plane that lies parallel to a straight line that may be imagined to pass through the outward convex points of the eyes, continued to a convenient length.

7. In fortification, the profile or representation of a work in all its parts, as they would appear if perpendicularly cut from top to bottom.