Chickenpox. Chickenpox usually starts with a skin rash mainly on the body and head.

Platelets. Platelets are manufactured in bone marrow and spend about 9 days in the bloodstream.

Acuity. The metric equivalent to 20/20 vision ins 6.6 vision.

Cilia. "Cilia" is Latin for "eyelash".

Ileum. The ileum is the final section of the small intestine and is usually 2-4 meters long in people.

Dehydration. Dehydration can be caused by the loss of body fluids or insufficient intake.