| Word | Definitions | Synonyms |
|---|---|---|
| undulation | (noun) (physics) a movement up and down or back and forth | Synonyms: wave |
| (noun) wavelike motion; a gentle rising and falling in the manner of waves | - | |
| (noun) an undulating curve | Synonyms: wave | |
| undutifulness | (noun) impiety characterized by lack of devotion to duty | - |