Wiktionary
n. (context inorganic compound English) An inorganic compound with the formula HCl. Forms hydrochloric acid when dissolved in water.
WordNet
n. a colorless corrosive gas: HCl
Wikipedia
The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colorless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric humidity. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl.
Usage examples of "hydrogen chloride".
The two aircraft which had flown into the smoke also went out of control as the hydrogen chloride fumes incapacitated their personnel, and both settled into the bay.
Spectrographic analysis which, given the quality of the vid on the crystal, was neither thorough nor reliable, tentatively identified the greenish fluid streamed at the cameras as an unknown compound with a dual base of hydrogen chloride and phosphoric acid.