One too many
Monocle
An eyeglass for only one eye
Bilingual
Using 2 languages
Monologue
A discourse by one person
Monarchy
A government with only one ruler
Polyglot
A linguist who knows many languages
Polygamy
Custom of having more than one spouse at the same time
Polygon
Closed figure with man angles
Polyandry
Custom of having more than one husband at the same time
Bifocal
Having 2 lenses
Polychromatic
Having many colors
Polymorphic
Having many forms
Polydactyl
Having more than the normal number of fingers or toes
Monogamy
Marriage to one person only
Bigamy
Marrying one person while already married to another
Bimonthly
Occurs every 2 months
Monochromatic
Only one color
Bipartisan
Representing 2 parties
Monotony
Sameness
Biennial
Something that occurs at 2-year intervals or lasts 2 years