Damp n.
 1. Moisture; humidity; fog; fogginess; vapor.
 Night . . . with black air
 Accompanied, with damps and dreadful gloom.   --Milton.
 2. Dejection; depression; cloud of the mind.
 Even now, while thus I stand blest in thy presence,
 A secret damp of grief comes o'er my soul.   --Addison.
    It must have thrown a damp over your autumn excursion.   --J. D. Forbes.
 3. Mining A gaseous product, formed in coal mines, old wells, pints, etc.
 Choke damp, a damp consisting principally of carbonic acid gas; -- so called from its extinguishing flame and animal life. See Carbonic acid, under Carbonic.
 Damp sheet, a curtain in a mine gallery to direct air currents and prevent accumulation of gas.
 Fire damp, a damp consisting chiefly of light carbureted hydrogen; -- so called from its tendence to explode when mixed with atmospheric air and brought into contact with flame.