Definition of: h, H

(āch) noun plural h's, H's or hs, Hs, aitch·es (ā′chiz)
1. The eighth letter of the English alphabet, from Phoenician cheth, which eventually developed into Greek eta, Roman H.
2. The sound of the letter h, a voiceless, glottal fricative. In a few English words of French origin, as heir, honor, hour, etc., initial h is still written but not pronounced; usage varies in certain other words, as herb, homage, etc., in which some persons pronounce the h and some do not. See ALPHABET.
—symbol Chem. Hydrogen (symbol H).