| Term | Definition |
| hibernal | wintery |
| hibernate | sleep throughout the winter |
| hierarchy | arrangement by rank or standing |
| hieroglyphic | picture writing |
| hilarity | boisterous mirth |
| hindmost | furthest behind |
| hindrance | block; obtacle |
| hinterlands | back country |
| hireling | one who serves for hire |
| hirsute | hairy |
| histrionic | theatrical |
| hoard | stockpile |
| hoary | white with age |
| hoax | trick; practical joke |
| holocaust | destruction by fire |
| holster | pistol case |
| homage | honor; tribute |
| homeostatis | tendency of a system to maintain relative stability |
| homespun | domestic; made at home |
| homily | sermon; serious warning |
| homogeneous | of the same kind |
| hone | sharpen |
| hoodwink | decieve; delude |
| horde | crowd |
| hortatory | encouraging; exhortive |
| horticulture | pertaining to cultivation of gardens |
| hostility | unfriendliness; hatred |
| hovel | shack; small, wretched house |
| hover | hang about |
| hubbub | confused uproar |
| hubris | arrogance; self-conceit |
| hue | color; aspect |
| hue and cry | outcry |
| humane | marked by kindness or consideration |
| humdrum | dull; monotonous |
| humid | damp |
| humility | humbleness of spirit |
| hummock | small hill |
| humus | substance formed by decaying vegetable matter |
| hurtle | crash; rush |
| husband | use sparingly; conserve; save |
| husbandry | frugality; thrift; agriculture |
| hybrid | mongrel; mixed breed |
| hydrophobia | fear of water |
| hyperbole | exaggeration; overstatement |
| hypercritical | excessively exacting |
| hypochondriac | person unduly worried about his health |
| hypocritical | pretending to be virtuous; decieving |
| hypothetical | based on assumptions or hypothesis; supposed |
| ichthyology | study of fish |
| icon | religious image; idol |
| iconoclastic | attacking cherished tradition |
| ideology | system of ideas characteristic of a group or culture |
| idiom | expression whose meaning as a whole differs from meaning of individual words |
| idiosynchrasy | individual trail, usually odd in nature |
| idolatry | worship of idols; excessive admiration |
| idyllic | charmingly carefree; simple |
| igneous | produced by fire; volcanic |
| ignite | kindle; light |
| ignoble | not worthy; not noble |
| ignominy | deep disgrace; shame and dishonor |
| illicit | illegal |
| illimitable | infinite |
| illuminate | brighten; clear up or make understandable |
| illusion | misleading vision |
| illusive | deceiving |
| illusory | deceptive; not real |
| imbalance | lack of balance or symmetry; diproportion |
| imbecility | weakness of mind |
| imbibe | drink in |
| imbroglio | complicated situation; painful or complex misunderstanding; entanglement; confused mass |
| imbue | saturate; fill |