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Related to rash: heat rash, Viral rash


nonspecific term for an eruption of the skinskin,
the flexible tissue (integument) enclosing the body of vertebrate animals. In humans and other mammals, the skin operates a complex organ of numerous structures (sometimes called the integumentary system) serving vital protective and metabolic functions.
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. It may result from skin allergy, skin irritation, or skin disease, or it may be a symptom of a systemic disease like measles, smallpox, or scarlet fever. A rash may appear as discolored spots or a general redness, or as blisters or pustules, either flat or raised above the surface of the skin. The rash may cause skin irritation—itching, tingling, burning, or pain—or it may not cause any discomfort. The appearance and distribution of a rash are often important factors for consideration in diagnosing a particular disease.



an eruption on the skin or mucous membrane of man, the cause of which can be either external and internal. Rashes accompany skin and other types of diseases. The external causes can be physical or chemical, while internal causes include diseases of the nervous and hemopoietic systems, metabolic disorders and functional disorders of certain organs (digestion, endocrine glands), infectious diseases (measles, scarlet fever), and allergic reactions (urticaria). Rashes may be primary or secondary. Primary rashes appear on previously normal skin or mucous membrane (spots, wheals, vesicles, pustules, tubercles). Secondary rashes appear as a further development of primary elements (pigmentation, scales, crusts, abrasions, ulcers, fissures, scars). The location, number, combination, color, shape, depth, and duration of the eruptions are helpful in diagnosing the disease.


A lay term for nearly any skin eruption, but more commonly for acute inflammatory dermatoses.
(mining engineering)
Very impure coal, so mixed with waste material as to be unsalable.


Pathol any skin eruption
References in classic literature ?
In another case I might think it rash, but I believe in your Harold, and I can see that he has had villainous treatment.
I am the Rash Act," was the sepulchral reply; "you may commit me.
Promise, my dear, you will do nothing rash, "said Benjamin, as he opened the door for me.
The rash reply flew out of my lips, like a bird set free from a cage.
It must always remain the great curiosity of history--a whim, a fantasy, an apparition, a thing unexpected and undreamed; and it should serve as a warning to those rash political theorists of to-day who speak with certitude of social processes.
From these and similar considerations, but chiefly from our ignorance of the geology of other countries beyond the confines of Europe and the United States; and from the revolution in our palaeontological ideas on many points, which the discoveries of even the last dozen years have effected, it seems to me to be about as rash in us to dogmatize on the succession of organic beings throughout the world, as it would be for a naturalist to land for five minutes on some one barren point in Australia, and then to discuss the number and range of its productions.
I feel how rash it is to differ from these great authorities, to whom, with others, we owe all our knowledge.
I would not be understood to suppose that the proceedings of the unhappy scapegrace, with his few profligate companions I have here introduced, are a specimen of the common practices of society - the case is an extreme one, as I trusted none would fail to perceive; but I know that such characters do exist, and if I have warned one rash youth from following in their steps, or prevented one thoughtless girl from falling into the very natural error of my heroine, the book has not been written in vain.
It is useless my addressing myself to a rash and headstrong old man who has a set purpose not to hear me.
Do you wish to know why I meant it, you rash and headstrong old woman?
And it was vexatious that Lawyer Gore was not more like him, but was a bald, round-featured man, with bland manners and fat hands; a game-cock that you would be rash to bet upon against Wakem.
Tulliver's views concerning it throughout the entire circle of his connections would necessarily take time; and at the beginning of February, when Tom was going to school again, there were scarcely any new items to be detected in his father's statement of the case against Pivart, or any more specific indication of the measures he was bent on taking against that rash contravener of the principle that water was water.