Gymna´sion (Gr.; from γυμνός, naked). Originally an open space, but in later times extensive courts and buildings, devoted to mental as well as bodily instruction and exercises.
He´lix, pl. hel´ices (Gr. anything twisted or spiral; from ἑλίσσω, to turn around). A spiral, particularly the volutes of the Ionic capital and the corner leaves and tendrils of the Corinthian.
Hexasty´los, adj. hex´astyle (from Gr. ἕξ, six, and στῦλος, column). A building, particularly a temple, upon the front of which are six columns.
Hip´podrome (Gr. ἱππόδρομος; from ἵππος, horse, and δρόμος, way). A course prepared for the races of horses and chariots.
Hypæ´thron, adj. hypæ´thral (Lat. hypæthrus; from Gr. ὑπό, under, and αἰθήρ, clear sky). Term applied to a temple supposed by some writers on Greek architecture to have been lighted from above, by an orifice through roof and ceiling.
Hyper´oön (Gr.). The upper stories of a house; particularly the galleries above the side-aisles in the interior of the Greek temple.
Hyp´ostyle (Gr. ὑπόστυλον; from ὑπό, under, and στῦλος, column). A space, with or without lateral enclosure, the ceiling of which rests upon columns.
Inci´sion. In architectural usage, the deep groove which separates the necking of the column from the upper drum of the shaft beneath. At times repeated to emphasize this separation.
Intercolumnia´tion (from Lat. inter, between, and columna, column). The open space between two columns, measured at the base. The measures are often taken from centre to centre of the columns.
Lacu´na, pl. lacunæ (Lat.; from Gr. λάκος, pit, originally anything hollow). A sunken panel in the under surface of any constructive feature, particularly of a horizontal ceiling.