"هند-اروپایي" refers to the Indo-European language family, which is one of the largest and most widely distributed language families in the world. It includes languages spoken in Europe and parts of Asia, such as English, Spanish, Hindi, and Russian. The family is believed to have originated from a common ancestral language, known as Proto-Indo-European, which was spoken thousands of years ago. Linguists categorize the Indo-European languages into several branches, including Germanic, Romance, Slavic, and Indo-Iranian. Each branch contains various languages that share similar grammatical structures and vocabulary. The study of these languages helps researchers understand historical migrations and cultural exchanges among different civilizations.