Found 2 items, similar to Hf.
English → English (WordNet) Definition: Hf Hf n 1: a gray tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons [syn: hafnium, atomic number 72] 2: 3 to 30 megahertz [syn: high frequency]
English → English (gcide) Definition: HF Hydrofluoric \Hy`dro*flu*or"ic\, a. [Hydro-, 2 + fluoric.] (Chem.) Pertaining to, or containing, hydrogen and fluorine; fluohydric; as, hydrofluoric acid. [1913 Webster] Hydrofluoric acid (Chem.), a colorless, mobile, volatile liquid, HF, very corrosive in its action, and having a strong, pungent, suffocating odor. It is produced by the action of sulphuric acid on fluorite, and is usually collected as a solution in water. It attacks all silicates, as glass or porcelain, is the agent employed in etching glass, and is preserved only in vessels of platinum, lead, caoutchouc, or gutta-percha. [1913 Webster]