The term STAMP COLLECTOR can be broken down into three crossword solutions: PASSPORT (8 letters), PHILATELIST (11 letters), and VISA (4 letters). A PASSPORT is an official document issued by a government that certifies the identity and nationality of its holder. A philatelist is someone who collects and studies postage stamps and other related items. A VISA is an endorsement on a PASSPORT indicating that the holder is allowed to enter, leave, or stay for a specified period of time in a country. Therefore, a stamp collector is someone who collects passports, postage stamps, and visas.