Aspiration is the friction made by the air passing through an open glottis (Eng. heaven /ˈhεvən/). In Classical Greek /h/ was a phoneme almost restricted to word-initial position. Archaic alphabets used the sign <Η> (originally called hêta, see Sch. D. T., p. 486, 32-35) for aspiration. Although <Η> was gradually abandoned after the 4th c. BCE, due to the extension of the Ionic script (in which <Η> was r…