De‐pres″sion (?), n. [L. depressio: cf. F. dépression.] 1. The act of depressing.
2. The state of being depressed; a sinking.
3. A falling in of the surface; a sinking below its true place; a cavity or hollow; as, roughness consists in little protuberances and depressions.
4. Humiliation; abasement, as of pride.
5. Dejection; despondency; lowness.
In a great depression of spirit. Baker.
6. Diminution, as of trade, etc.; inactivity; dullness.
7. (Astron.) The angular distance of a celestial object below the horizon.
8. (Math.) The operation of reducing to a lower degree; — said of equations.
9. (Surg.) A method of operating for cataract; couching. See Couch, v. t., 8.
Angle of depression(Geod.), one which a descending line makes with a horizontal plane. — Depression of the dewpoint(Meteor.), the number of degrees that the dew-point is lower than the actual temperature of the atmosphere. — Depression of the pole, its apparent sinking, as the spectator goes toward the equator. — Depression of the visible horizon. (Astron.) Same as Dip of the horizon, under Dip.
Syn. — Abasement; reduction; sinking; fall; humiliation; dejection; melancholy.