A person who is concerned with the scientific study of the history, symbolism, and usage of flags or, by extension, any interest in flags in general is called a vexillologist.

Scholars point out that the word vexillology is a synthesis of the Latin word vexillum ("flag") and the Greek suffix - logia ("study.") The constitution of the International Federation of Vexillological Associations (known by its French acronym, FIAV) formally defines vexillology as "the creation and development of a body of knowledge about flags of all types, their forms and functions, and of scientific theories and principles based on that knowledge."

The person best known for being a vexillologist was the U.S. scholar and student of flags Whitney Smith, Jr. (1940 - 2016). In 1957 he moved to formalize and organize various flag organizations. They included the first International Congress of Vexillology, the North American Vexillological Association, and International Federation of Vexillological Associations. The term vexillology was conceived by Smith in 1958.

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