Ammonia solution is a commonly used alkaline solution with a characteristic pungent odor. It has many synonyms, which can be used interchangeably depending on the context. Some of these synonyms include ammonium hydroxide, aqua ammonia, ammonia water, spirit of hartshorn, and ammonia liquor. These synonyms describe the same chemical compound which consists of ammonia gas dissolved in water. Ammonia solution is widely used in industries such as cleaning, agriculture, and food production. It is also used in several household cleaning products for its high alkalinity and cleaning properties. In summary, ammonium hydroxide, aqua ammonia, ammonia water, spirit of hartshorn, and ammonia liquor are synonyms for ammonia solution, which is an essential compound with various industrial and household uses.