Simplify the following text for a Grade 12 native English-speaking person.
Original: Ammonia solution , also known as ammonium hydroxide , ammonia water , ammonical liquor , ammonia liquor , aqua ammonia , aqueous ammonia , or simply ammonia , is a solution of ammonia in water .
Simplified: Ammonium hydroxide can refer to household ammonia or a more concentrated solution of ammonia in water .