monochrome- having one color; a painting, design, photo, or outfit that is only one color or shades of one color

 

monocle- en 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