Definition of undulation
1a : a rising and falling in wavesb : a wavelike motion to and fro in a fluid or elastic medium propagated continuously among its particles but with little or no permanent translation of the particles in the direction of the propagation : vibration
2 : the pulsation caused by the vibrating together of two tones not quite in unison
3 : a wavy appearance, outline, or form : waviness
First Known Use of undulation
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