| Term | Definition |
| lout | clumsy person |
| low | moo |
| lucid | easily understood; clear; intelligible |
| lucrative | profitable |
| lucre | money |
| ludicrous | laughable; trifling |
| lugubrious | mournful |
| lull | moment of calm |
| lumber | move heavily and clumsily |
| lumen | unit of light energy |
| luminary | celebrity; dignitary |
| luminous | shining; issuing light |
| lunar | pertaining to the moon |
| lunge | make a quick forward dive or reach; thrust |
| lurid | wild; sensational; graphic; gruesome |
| lurk | stealthily lie in waiting; slink; exist unperceived |
| luscious | pleasing to taste or smell |
| luster | shine; gloss |
| lustrous | shining |
| luxuriant | abundant; rich and splendid; fertile |
| macabre | gruesome; grisly |
| mace | ceremonial staff; club-like medieval weapon |
| macerate | soften by soaking in liquid; waste away |
| Machiavellian | crafty; double dealing |
| machinations | evil schemes or plots |
| maculated | spotted; stained |
| madrigal | pastoral song |
| maelstrom | whirlpool |
| magisterial | authoritative; imperious |
| magnanimity | generosity |
| magnate | person of prominence or influence |
| maim | mutilate; injure |
| magnate | person of prominence or influence |
| magniloquent | boastful, pompous |
| magnitude | greatness; extent |
| maladroit | clumsy; bungling |
| malady | illness |
| malaise | uneasiness; vague feeling of ill health |
| malapropism | comic misuse of words |
| malcontent | person dissatisfied with existing state of affairs |
| malediction | curse |
| malefactor | evildoer; criminal |
| malevolent | wishing evil |
| malfeasance | wrongdoing |
| malicious | hateful; spiteful |
| malign | speak evil of; bad ; defame |
| malignant | injurious; tending to cause death; aggressively malevolent |
| malingerer | one who escapes illness to escape duty |
| malleable | capable of being shaped into by pounding; impressionable |
| malodorous | foul-smelling |
| mammal | vertebrate animal whose females suckles its young |
| mammoth | gigantic; enormous |
| manacle | restrain; handcuff |
| mandate | order; charge |
| mandatory | Required or commanded by authority; obligatory |
| mangy | shabby; wretched |
| maniacal | raging mad; insane |
| manifest | evident; visible; obvious |
| manifestation | outward demonstration; indication |
| manifesto | declaration; statement of policy |
| manifold | numerous; varied |
| manipulate | operate with one's hand; control or play upon (people, forces, etc) artfully |
| mannered | affected; not natural |
| manumit | emancipate; free from bondage |
| marital | pertaining to marriage |
| maritime | bordering on the sea; nautical |
| marked | noticeable; targeted for vengeance |
| marred | damaged; disfigured |
| marshal | put in order |
| marsupial | one of a family of mammals that nurse their offspring in a pouch |
| martial | warlike |
| martinet | One who imposes or favors absolute obedience to authority: |
| martyr | one who voluntarily suffers for his or her religion or cause; great suferer |
| masochist | person who enjoys his own pain |
| masticate | chew |
| materialism | preoccupation with physical comforts and things |
| maternal | motherly |
| matriarch | woman who rules a family or larger social group |
| matriculate | enroll ( in college or graduate school) |
| matrix | point of origin; array of numbers or algebraic symbols; mold or die |
| maudlin | effusively sentimental |
| maul | handle roughly |