Undulation (noun)

A waving or wavelike motion.

Origin:

From french undulation, from latin undulatio, from undulare ("to wave").

Examples:

1. The undulation of the flag in the wind was graceful.
2. The undulation of the snake as it slithered was fascinating.
3. Many undulations in nature are caused by wind, water, or other factors.
4. The undulation of the dancer was graceful and fluid.
5. The undulation of the sea was soothing to watch.