1.The deficiency or absence of perspiration or sweating: Grady appeared to have a condition of anhidrosis because he was not sweating even on very hot and humid days.

Dr. Clay told Doyle that it was not a healthy condition to suffer from anhidroses because his skin needed to sweat in order for his body to be healthy.

2. Absence of sweating in horses, a condition more noticeable in hot climates; affected animals develop severe dyspnea (bad breathing) and cannot work: The farmer was concerned because his horses appeared to be ill so Conrad called the veterinarian who told him that they were suffering with anhidrosis.
3. Absence or deficiency of sweating; in humans this is usually due to the absence or paralysis of the sweat glands or to some kind of obstruction of the sweat ducts: When a person experiences anhidrosis, it can be a dangerous health concern.

For some people, having anhidroses may seem to be a blessing; but it isn't, because to sweat makes it possible for us to stay cooler. Anhidrosis creates a dangerous inability for people to tolerate heat.