undulant UN-juh-lunt; UN-dyuh-, adjective:

Resembling waves in form, motion, or occurrence; undulating.

[From Late Latin undula, small wave, diminutive of Latin unda, wave; see wed-1 in Indo-European Roots.]

My wakefulness is coming in a slow, undulant progression….today and yesterday, I sort of just ebbed into it.

Good morning! Spongebob is on!