| A | B | 
|---|
| monochrome | having one color; a painting, design, photo, or outfit that is only one color or shades of one color | 
| monocle | an eyeglass for one eye | 
| monolingual | speaking or writing only one language | 
| monolith | something made out of one single large block or piece of stone; one single stone monument | 
| monologue | a long speech given by one person | 
| monophobia | an abnormal fear of being the only one there; fear of being alone | 
| monopoly | control of a product or service by one company | 
| monorail | a track for subway or train cars that only has one rail | 
| monosyllabic | having only one syllable | 
| monotone | a speech in which every word has one tone of voice |