Afghan (name)

The ethnonym Afghan (افغان Afġān) has been used in the past to refer to members of Pashtun tribes, and that usage persists in some places in Afghanistan. The name Afghanistan (افغانستان Afġānistān; Afghan + -stan) is a derivation from the ethnonym Afghan, originally in the loose meaning "land of the Pashtuns" and referred to the Pashtun tribal areas south of the Hindu Kush. Initially they were known as "Abgan" during 1st and 2nd century, later in 3rd century, the Sassanids mention an eastern tribe called Abgân, which is attested in its Arabic form (Afġān) in the 10th century Ḥudūd al-ʿĀlam. Through the nineteenth century, the term "Afghan" was used by various writers as a synonym for "Pashtun", but such usage now is rare in English.

Since the Afghan Constitution of 1964, "Afghan" officially refers to every citizen of the state of Afghanistan, regardless which ethnic group the individual belongs to.

The earliest mention of the name Afghan (Abgân) is by Shapur I of the Sassanid Empire during the 3rd century CE, which is later recorded in the 6th century in the form of "Avagāṇa" (अवगाण) by the Indian astronomer Varāha Mihira in his Brihat-samhita.

The Encyclopædia Iranica explains:

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