| honorarium | A token fee or payment to a professional man for services. |
| hoodwink | To deceive. |
| horde | A gathered multitude of human beings. |
| hosiery | A stocking. |
| hospitable | Disposed to treat strangers or guests with generous kindness. |
| hospitality | The practice of receiving and entertaining strangers and guests with kindness. |
| hostility | Enmity. |
| huckster | One who retails small wares. |
| humane | Compassionate. |
| humanitarian | A philanthropist. |
| humanize | To make gentle or refined. |
| humbug | Anything intended or calculated to deceive or mislead. |
| humiliate | To put to shame. |
| hussar | A light-horse trooper armed with saber and carbine. |
| hustle | To move with haste and promptness. |
| hybrid | Cross-bred. |
| hydra | The seven- or nine-headed water-serpent slain by Hercules. |
| hydraulic | Involving the moving of water, of the force exerted by water in motion. |
| hydrodynamics | The branch of mechanics that treats of the dynamics of fluids. |
| hydroelectric | Pertaining to electricity developed water or steam. |
| hydromechanics | The mechanics of fluids. |
| hydrometer | An instrument for determining the density of solids and liquids by flotation. |
| hydrostatics | The branch of science that treats of the pressure and equilibrium of fluids. |
| hydrous | Watery. |
| hygiene | The branch of medical science that relates to improving health. |
| hypercritical | Faultfinding. |
| hypnosis | An artificial trance-sleep. |
| hypnotic | Tending to produce sleep. |
| hypnotism | An artificially induced somnambulistic state in which the mind readily acts on suggestion. |
| hypnotize | To produce a somnambulistic state in which the mind readily acts on suggestions. |
| hypocrisy | Extreme insincerity. |
| hypocrite | One who makes false professions of his views or beliefs. |
| hypodermic | Pertaining to the area under the skin. |
| hypotenuse | The side of a right-angled triangle opposite the right angle. |
| hypothesis | A proposition taken for granted as a premise from which to reach a conclusion. |
| hysteria | A nervous affection occurring typically in paroxysms of laughing and crying. |
| ichthyic | Fish-like. |
| ichthyology | The branch of zoology that treats of fishes. |
| ichthyosaurs | A fossil reptile. |
| icily | Frigidly. |
| iciness | The state of being icy. |
| icon | An image or likeness. |
| iconoclast | An image-breaker. |
| idealize | To make to conform to some mental or imaginary standard. |
| idiom | A use of words peculiar to a particular language. |
| idiosyncrasy | A mental quality or habit peculiar to an individual. |
| idolize | To regard with inordinate love or admiration. |
| ignoble | Low in character or purpose. |
| ignominious | Shameful. |
| Iliad | A Greek epic poem describing scenes from the siege of Troy. |