Blain, in farriery, a distemper incident to horses and cattle, consisting of a tumor which grows on the root of the tongue, and swells to such a size as frequently to stop respiration. It is caused by excessive irritation and heat of the stomach, and discovers itself by the animals gaping, and hanging out its tongue. The method of cure is as follows: Lay the beast on the ground, open the tumor, and wash it with vinegar and a little salt.