Based on context, what is a mummer? What words and phrases does Poe use to describe the mummer and what do these words mean?

A mummer resembles someone with the red death disease. Its face is corpse like and dabbed with blood. The mummer appears mysteriously and stalks back and forth. It resembles the grim reaper and is the red death.

The figure was tall and gaunt, and shrouded from head to foot in the habiliments of the grave. The mask which concealed the visage was made so nearly to resemble the countenance of a stiffened corpse that the closest scrutiny must have had difficulty in detecting the cheat.