ptilosis noun2 •The appearance or study of feathers on a bird, including factors such as their texture or shape.Pterylography must be based on the distribution of the follicles, for the ptilosis as seen externally does not reflect the actual pterylosis. — 2013 •Loss of the eyelashes, due to ulceration or other damage to the follicles.This is an aggravated form of the last disease, and presents ulceration and induration of the edges of the eye: lids, so as to cause the cilia, or lashes to fall out—ptilosis. — 1836 formsptiloses
