In this Grade 4 lesson from Vocabulary from Classical Roots Book A, students explore the Latin and Greek roots MONOS, UNUS, DUO, and DUPLEX to understand how the concept of numbers shapes word meaning. Key vocabulary terms including monologue, monarch, monopoly, unanimous, unilateral, and duplex are introduced with definitions, example sentences, and related word forms. Students practice connecting root meanings to spelling and usage, building a foundation for recognizing number-based roots across a wide range of English words.
Section 1
The Power of One: MONOS
These words all come from the Greek root MONOS, meaning "one." They describe things that are singular, from a single ruler to a single giant stone.
| Word | Definition |
|---|---|
| monologue | (n.) a long speech by one person |
| monarch | (n.) a ruler such as a king or queen |
| monogram | (n.) a design made from a person’s initials |
| monopoly | (n.) complete control over a product or service |
| monolith | (n.) a large single block of stone |
Section 2
United as One: UNUS
Next up are words from the Latin root UNUS, which also means "one." These words focus on the idea of unity or one-sidedness.
| Word | Definition |
|---|---|
| unanimous | (adj.) in complete agreement |
| unilateral | (adj.) done by one side or person only |
Section 3
Seeing Double: DUO & DUPLEX
Now we're seeing double with the Latin roots DUO ("two") and DUPLEX ("twofold"). These words are all about pairs and copies.
| Word | Definition |
|---|---|
| duplex | (n.) a building with two living units |
| duplicate | (v.) to make an exact copy |
Section 4
The Power of Two: BI
Finally, the Latin root BI also means "two." These words describe things involving two sides, two parties, or two parts.
| Word | Definition |
|---|---|
| bilateral | (adj.) involving two sides or groups |
| bipartisan | (adj.) involving two political parties |
| bisect | (v.) to divide into two equal parts |
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Section 1
The Power of One: MONOS
These words all come from the Greek root MONOS, meaning "one." They describe things that are singular, from a single ruler to a single giant stone.
| Word | Definition |
|---|---|
| monologue | (n.) a long speech by one person |
| monarch | (n.) a ruler such as a king or queen |
| monogram | (n.) a design made from a person’s initials |
| monopoly | (n.) complete control over a product or service |
| monolith | (n.) a large single block of stone |
Section 2
United as One: UNUS
Next up are words from the Latin root UNUS, which also means "one." These words focus on the idea of unity or one-sidedness.
| Word | Definition |
|---|---|
| unanimous | (adj.) in complete agreement |
| unilateral | (adj.) done by one side or person only |
Section 3
Seeing Double: DUO & DUPLEX
Now we're seeing double with the Latin roots DUO ("two") and DUPLEX ("twofold"). These words are all about pairs and copies.
| Word | Definition |
|---|---|
| duplex | (n.) a building with two living units |
| duplicate | (v.) to make an exact copy |
Section 4
The Power of Two: BI
Finally, the Latin root BI also means "two." These words describe things involving two sides, two parties, or two parts.
| Word | Definition |
|---|---|
| bilateral | (adj.) involving two sides or groups |
| bipartisan | (adj.) involving two political parties |
| bisect | (v.) to divide into two equal parts |
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter