What is a hinky pinky for a caterpillar's movement?

A hinky pinky for a caterpillar's movement is "wiggly squiggly." Hinky pinkies are playful rhyming riddles where the answer consists of two Words that rhyme and fit the given clue. In this case, "wiggly" captures the caterpillar's characteristic movement, while "squiggly" further emphasizes its undulating motion.