n. 1. A hydro-aëroplane. [ obsolescent ] [ Webster 1913 Suppl. ]

2. hydroelectric power; -- also used attributively. [ PJC ]

. (Aëronautics) An aëroplane with a boatlike or other understructure that enables it to travel on, or to rise from the surface of, a body of water by its own motive power; -- now usually referred to as a seaplane. [ obsolescent ] [ Webster 1913 Suppl. +PJC ]

n. [ Hydro-, 1 + barometer. ] An instrument for determining the depth of the sea water by its pressure. [ 1913 Webster ]

n. [ Hydro-, 2 + bilirubin. ] (Physiol. Chem.) A body formed from bilirubin, identical with urobilin. [ 1913 Webster ]

n. A hydro-aëroplane having two supporting planes. [ Webster 1913 Suppl. ]

‖n. pl. [ NL., fr. Gr. "y`dwr water + &unr_; gills.] (Zool.) An extensive artificial division of gastropod mollusks, including those that breathe by gills, as contrasted with the Pulmonifera. -- Hy`dro*bran"chi*ate a. [ 1913 Webster ]

n. (Chem.) Same as Hydrobromide. [ 1913 Webster ]

a. [ Hydro-, 2 + bromic. ] (Chem.) Composed of hydrogen and bromine; as, hydrobromic acid. [ 1913 Webster ]

Hydrobromic acid (Chem.), a colorless, pungent, corrosive gas, HBr, usually collected as a solution in water. It resembles hydrochloric acid, but is weaker and less stable. Called also hydrogen bromide. [ 1913 Webster ]

n. (Chem.) A compound of hydrobromic acid with a base; -- distinguished from a bromide, in which only the bromine unites with the base. [ 1913 Webster ]

n. [ Hydro-, 2 + carbon. ] (Chem.) A compound containing only hydrogen and carbon, as methane, benzene, etc.; also, by extension, any of their derivatives. [ 1913 Webster ]

Hydrocarbon burner,
furnace,
stove, a burner, furnace, or stove with which liquid fuel, as petroleum, is used. [ 1913 Webster ]