Here's what we know:
* "Willies" is a slang term for a feeling of nervousness, unease, or fear, often accompanied by a physical sensation of goosebumps or chills. It likely originated from the verb "to will" which means "to desire something strongly" and possibly implies a sense of being overwhelmed or anxious.
* "Creeps" refers to a feeling of unease, discomfort, or fear, often caused by something unsettling or strange. It may be related to the word "creep" which describes a slow, gradual movement or feeling of uneasiness.
The exact origin of these phrases is unclear, but they likely arose in spoken English as informal expressions of uncomfortable feelings. They became popular in the early 20th century and have since become common slang terms.
Here are some theories about the origin of these phrases:
* "Willies" could be a shortened form of "willies-nillies" or "willies-waws" which were used in the 18th and 19th centuries to describe a state of agitation or nervous excitement.
* "Creeps" might be related to the word "creeping" which can be used to describe the feeling of being stalked or watched. It could also be linked to the idea of something "creeping" into your mind and making you feel uneasy.
While the precise origin remains unknown, it's clear that both "gives you the willies" and "gives you the creeps" are effective ways to convey a sense of uneasiness or fear in a casual and relatable way.