"Anna Mary Robertson Moses" is not a single English word, but the full name of an important American artist, often known simply as "Grandma Moses." Here’s a simple explanation:
Anna Mary Robertson Moses (1860-1961) was a famous American painter known for her colorful and simple paintings that depict rural life and scenes. She started painting at an older age (in her 70s) and became well-known for her unique style, which is often described as "primitive" or "folk art."
Anna Mary Robertson Moses was a significant figure in American art, and her work continues to inspire many people.