| Term | Definition |
| HERMETIC | tightly sealed |
| HETEROGENEOUS | composed of unlike parts; different; diverse |
| HOARY | very old; whitish or gray from age |
| HOMOGENEOUS | of a similar kind |
| HUSBAND | to manage economically; to use sparingly |
| HYPERBOLE | purposeful exaggeration for effect |
| ICONOCLAST | one who opposes established beliefs, customs, and institutions |
| IDIOSYNCRASY | peculiarity of temperament; eccentricity |
| IGNOBLE | having low moral standards; not noble in character; mean |
| IMBUE | to infuse, dye, wet, or moisten |
| IMPASSE | blocked path; dilemma with no solution |
| IMPECUNIOUS | poor; having no money |
| IMPERTURBABLE | not capable of being disturbed |
| IMPERVIOUS | impossible to penetrate |
| IMPETUOUS | quick to act without thinking |
| IMPIOUS | not devout in religion |
| IMPLACABLE | unable to be calmed down or made peaceful |
| IMPRECATION | a curse |
| IMPUGN | to call into question; to attack verbally |
| INCARNADINE | blood-red in color |
| INCHOATE | not fully formed; disorganized |
| INCULCATE | to teach; impress in the mind |
| INDOLENT | habitually lazy or idle |
| INEXORABLE | inflexible; unyielding |
| INGENUOUS | showing innocence or childlike simplicity |
| INGRATE | ungrateful person |
| INGRATIATE | to gain favor with another by deliberate effort; to seek to please somebody so as to gain an advantage |
| INIMICAL | hostile; unfriendly |
| INIQUITY | sin; evil act |
| INNOCUOUS | harmless |
| INQUEST | an investigation; an inquiry |
| INSIPID | lacking interest or flavor |
| INSURRECTION | rebellion |
| INTER | to bury |
| INTERREGNUM | period between reigns |
| INTRACTABLE | not easily managed or manipulated |
| INTRANSIGENT | uncompromising; refusing to be reconciled |
| INTREPID | fearless; resolutely courageous |
| INUNDATE | to overwhelm; to cover with water |
| INURE | to harden; accustom become used to |
| INVECTIVE | abusive language |
| INVESTITURE | ceremony conferring authority |
| INVIDIOUS | envious, obnoxious, or offensive; likely to promote ill-will |
| IRASCIBLE | easily made angry |
| ITINERANT | wandering from place to place; unsettled |
| JARGON | nonsensical talk; specialized language |
| JETTISON | to discard; get rid of as unnecessary or encumbering |
| JINGOISM | belligerent support of one's country |
| JOCULAR | playful; humorous |
| JUDICIOUS | sensible; showing good judgement |
| JUNCTURE | point of time, especially where two things are joined |
| KEEN | having a sharp edge; intellectually sharp; perceptive |
| KINDLE | to set fire to or ignite; excite or inspire |
| KINETIC | relating to motion; characterized by movement |
| KNELL | sound of a funeral bell; omen of death or failure |
| KUDOS | fame, glory, or honor |
| LACHRYMOSE | tearful |
| LACONIC | using few words |
| LAMENT | to express sorrow; to grieve |
| LAMPOON | to ridicule with satire |
| LANGUID | lacking energy; indifferent; slow |
| LAPIDARY | relating to precious stones or the art of cutting them |
| LARCENY | theft of property |
| LARGESS | generous giving (as of money) to others who may seem inferior |
| LASSITUDE | a state of diminished energy |
| LATENT | potential that is not readily apparent |
| LAUD | to give praise; to glorify |
| LAVISH | extremely generous or extravagant; giving unsparingly |
| LEERY | suspicious |
| LEGERDEMAIN | trickery |
| LETHARGIC | acting in an indifferent or slow, sluggish manner |
| LEVITY | an inappropriate lack of seriousness; overly casual |
| LIBERAL | tolerant or broad-minded; generous or lavish |
| LIBERTINE | a free thinker, usually used disparagingly; one without moral restraint |
| LICENTIOUS | immoral; unrestrained by society |
| LIMPID | clear; transparent |
| LIONIZE | to treat as a celebrity |
| LISSOME | easily flexed; limber; agile |
| LISTLESS | lacking energy and enthusiasm |
| LIVID | discolored from a bruise; reddened with anger |
| LOQUACIOUS | talkative |
| LUCID | clear and easily understood |
| LUGUBRIOUS | sorrowful; mournful; dismal |
| LUMBER | to move slowly and awkwardly |
| LUMINOUS | bright; brilliant; glowing |
| MACHINATION | plot or scheme |
| MAELSTROM | whirlpool; turmoil; agitated state of mind |
| MAGNATE | powerful or influential person |
| MALEDICTION | a curse; a wish of evil upon another |
| MALINGER | to evade responsibility by pretending to be ill |
| MALLEABLE | capable of being shaped |
| MANNERED | artificial or stilted in character |
| MAR | to damage or deface; spoil |
| MARTINET | strict disciplinarian; one who rigidly follows rules |
| MAUDLIN | overly sentimental |
| MENDACIOUS | dishonest |
| MENDICANT | beggar |
| MERCURIAL | quick, shrewd, and unpredictable |
| MERETRICIOUS | gaudy; falsely attractive |
| METAPHOR | figure of speech comparing two different things |