This is the 41st most frequent Persian word.
تهران
Tehran: The capital city of Iran.
In this sentence, 'تهران' is used as a proper noun referring to a specific location—Tehran, the capital city of Iran.
من دیروز به تهران سفر کردم.
I traveled to Tehran yesterday.
Here, 'تهران' appears as the subject of the sentence, emphasizing its characteristic as a city within Iran.
تهران یکی از پرجمعیتترین شهرهای ایران است.
Tehran is one of the most populous cities in Iran.
In this context, 'تهران' is employed to denote the location where the depicted scenario of cultural and historical blending occurs.