pilo-, pil-, pili- +

A reference to, or covered with hair: After the cat had jumped off the pillow after having slept there for a long time, the pillow had a rather pilar look and had to be vacuumed to remove all the cat's hair!

1. Of or relating to hair or a hair; hairy: Mrs. Smith remember the robber as being very pilary with big black-rimmed glasses.
2. Concerning something covered with hairs, especially fine soft onesThe newborn kittens were very pilary with such very smooth and silky hair.

A hairline fracture that may be found in skull bones: After the old skeleton had been retrieved from the grave, the archeologist discovered that there was a pilation in the right side of the skull.

Pertaining to something covered with hair: The little puppies were all pileous and so nice to pet!

The top of a bird's head from the bill to the nape: There were lots of birds at the bird feeder and Mrs. Lawson could tell them all apart just by looking at their pileum which all had different colors and markings.

A pileum is the top of a bird's head, from the nape (back part of the neck) to the bill (bird's beak or mouth part).

The formation and growth of hair: In her studies, Mildred chose a class covering the area of piliation where she could learn about the production and growth of hair.

1. Referring to a plant part that ends in a hair or hairs: Pliferous plant parts are covered in fine hairs, or have hairs growing at the tip.
2. Concerning the outer layer of the root epidermis of plants that produces root hairs: In his botany class, Joe learned all about the piliferous parts of plants that are responsible for root hair growth

Referring to a slender shape, fine as a hair; trichoid: Some plant parts are piliform because they are quite hair-like and feel like down.

The passing of urine embodying hair-like strands or fibers: After being diagnosed by the doctor, Mark was told that he had a case of pilimiction, or the fact that his urine contained threads of mucus, and that this condition could be treated.

Of the nature of hair; hairy: Mrs. Black asked her husband to shave off his piline beard because it was becoming much too undignified.

Referring to hair: In medicine, a piloerection of the hair follicles, is the contraction of hair or pilo muscles causing goosebumps.

Various words about "hair" as seen in this pilo unit.

Pertaining to a tumor that contains hair: A pilocystic tumor is cyst-like and includes hairs, for example certain dermoid tumors.

Pertaining to cells with obvious and pronounced external hair-like structures: In medicine, such pilocytic forms of cells can be detected with a microscope and such cells look like filaments or hair

1. A skin reaction caused by erection of the hair follicles: Piloerection can be caused by cold or shock due to contraction of the "arrector pili" muscles. This causes transient roughness of the skin.
2. An involuntary erection or bristling of hairs due to a sympathetic reflex: Piloerection is usually triggered by cold, shock, or fright, or due to a sympathomimetic agent.

"Goose bumps" (American English), also called "goose pimples", "goose flesh" (British English), "chicken skin" (Hawaiian Pidgin), or "cutis anserina", are the bumps on a person's skin at the base of body hairs which involuntarily develop when a person is cold or experiences strong emotions, such as fear. The reflex of producing goose bumps is known as "horripilation" or "pilomotor reflex". It occurs in humans and in other mammals.

Piloerection starts when a stimulus such as cold or fright causes a discharge from the (involuntary) nervous system that triggers a contraction of the little "arrectores pilorum" muscles. Contraction of these muscles elevates the hair follicles above the rest of the skin so the hair seems to "stand on end".

Resembling hair; hair-like: The down of little chicks were of a piloid structure which were so soft and fluffy.