Damp (dămp), n. [Akin to LG., D., & Dan. damp vapor, steam, fog, G. dampf, Icel. dampi, Sw. damb dust, and to MNG. dimpfen to smoke, imp. dampf.] 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.