1. The act of pressing down; or the state of being pressed down; a low state.
2. A hollow; a sinking or falling in of a surface; or a forcing inwards; as roughness consisting in little protuberances and depressions; the depression of the skull.
3. The act of humbling; abasement; as the depression of pride; the depression of the nobility.
4. A sinking of the spirits; dejection; a state of sadness; want of courage or animation; as depression of the mind.
5. A low state of strength; a state of body succeeding debility in the formation of disease.
6. A low state of business or of property.
7. The sinking of the polar star towards the horizon, as a person recedes from the pole towards the equator. Also, the distance of a star from the horizon below, which is measured by an arch of the vertical circle or azimuth, passing through the star, intercepted between the star and the horizon.
8. In algebra, the depression of an equation, is the bringing of it into lower and more simple terms by division.