undulation.

A wave-like rise and fall in a surface, shape or movement.

Use it for

Words that belong together

• gentle undulation
• undulation of the ground

On the page

A gentle undulation ran across the field toward the distant ridge.

The undulation of the ground hid the path at intervals without breaking its course.

Usage notes

Primary category: setting / description. Forms: Singular undulation; plural undulations. Also uncountable. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Writing functions: spatial orientation, setting description, material description, contrast. Disciplines: descriptive writing, physical setting, spatial analysis. Commonness: moderately common.