Which word refers to shrinking back in fear or cowering?

The term that best encapsulates the idea of shrinking back in fear or cowering is "quail." When someone quails, they exhibit a physical response to fear, often characterized by a retreat or withdrawal from a threatening situation. This word vividly conveys the essence of fear-induced hesitation or cowardice, as it suggests not just fear but a specific response to that fear.

In contrast, while "cower," "quake," and "tremble" also relate to fear, they do not carry the same connotation of a retreat. "Cower" focuses on the action of huddling down, which can imply a defensive posture rather than a withdrawal. "Quake" and "tremble" describe physical reactions to fear but do not inherently imply the act of shrinking away from a threat. Therefore, "quail" specifically captures the combination of fear and the retreating motion that is central to the question.