With higher levels of anxiety of late people might react strongly verbally. We call this the Barking Dog Syndrome.
The Barker may not know a better way to delay or discourage unwanted attention. A display of Barking Dog Syndrome is therefore an immediate demand for space. That snapping word, curse or harsh tone is an expression of frustration and a warning that the person cannot engage well with you now. Back away and allow them that time and space.