Someone who collects stamps is called a philatelist. This word is of Greek origin where it means one who loves pre paid taxes. A person who studies or is an enthusiast of stamps is also known as a philatelist.
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A philatelist is a person who studies and collects stamps. Stamp collecting is a big hobby and can turn into a lucrative one. Some philatelists collect specific types of stamps such as air mail stamps and the type of stamps printed to honor public figures.