Become a dinosaur
Wavy is correct.
If you are referring to wavy hair, or a wavy line, it is "ondulé/-e."
My guess is that when the baby starts clawing at your insides, that you will become aware of the existence of its fingernails.
As undulate means to rise and fall, become wavy or rippled, an antonym would be to "roughen".
Wavy.
a wavy rectangle
She has wavy hair. The wavy pattern of that wallpaper is making me feel ill.
Wavy in Spanish is ONDULADO which means curly
A curve that is wavy. Like a potato.
penta-fingernails
you duct tape their fingernails and when they forget that the pick their fingernails and then its all done