| A | B |
| monorail | a track for subway or train cars with only ONE rail |
| monotone | speech where every sound is the same (ONE sound) |
| monocle | an eyepiece that only goes over ONE eye |
| monolingual | a person who can speak or write only ONE language |
| monopoly | having control over one product or service by ONE company |
| monolith | something make out of ONE single large piece of stone; stone monument |
| mono- | one |
| monologue | a long speech given by ONE person |
| monophobia | fear of being the only ONE there |
| monochrome | having ONE color, painting, design, outfit, etc. or shade of ONE color |
| monosyllabic | having only ONE syllable |