HORNBOOK n.
their letters and rudiments; -- so called because a sheet of horn covered the small, thin board of oak, or the slip of paper, on which the alphabet, digits, and often the Lord's Prayer, were written or printed; a primer. "He teaches boys the hornbook." Shak.
HOUND n.
und, deerhound, but also used for various breeds of fleet hunting dogs, as the greyhound, boarhound, etc. Hounds and greyhounds, mongrels, spaniels, curs. Shak.
HYDROPLANE n. 3 definitions
A plane, or any of a number of planes, projecting from the hull of a submarine boat, which by being elevated or depressed cause the boat, when going ahead, to sink or rise, after the manner of an aëroplane.