Definition & Meaning of "[ruffle] {one's} feathers"

What is the origin of the idiom "ruffle one's feathers" and when to use it?

The exact origin of the phrase "ruffle one's feathers" is unclear, but it likely derives from observations of actual birds and their physical response to agitation or disturbance. When birds are agitated or feel threatened, their feathers may become ruffled, appearing disheveled or raised. It is often used to describe interpersonal conflicts, disagreements, or instances where someone feels offended or provoked. This idiom can be employed in personal relationships, professional settings, or social interactions to convey the idea of emotional disturbance or irritation caused by external factors.