Eponym
![The mythological Greek hero Orion is the eponym of the constellation Orion, shown here, and thus indirectly of the Orion spacecraft.[1]](/Images/godic/202412/21/Orion_Head_to_Toe1339.jpg")
An eponym is a person, place, or thing for whom or for which something is named, or believed to be named. For example, Elizabeth I of England is the eponym of the Elizabethan era.
Many genericized trademarks such as aspirin, heroin and thermos are based on their original brand eponyms.