The word "rash" is often used to describe a skin condition that leaves red, raised and itchy spots on the skin. However, there are several other words that can be used interchangeably for the same purpose. Some of the synonyms for the word "rash" include eruption, outbreak, skin irritation, dermatitis, hives, and redness. Each of these words help to describe a skin condition where there is a sudden occurrence of bumps or redness on the skin. Using a variety of synonyms for "rash" can help to add variation and interest to your writing, and can help readers to better understand the condition you are describing.