In Armenian mythology, Azhdahak(Armenian: Աժդահակ)is a men-vishap or men-dragon.
Typically, Vishaps thrive in high mountains, big lakes, sky and clouds. They usually roar when they soar on the sky or descend on the lakes and sweep away everything that block their way. A thousand year old vishap is believed to absorb the whole world.
Based on the account of Movses Khorenatsi, Azhdhak was a king of Marrs (Medes) and the grandfather of Cyrus. He was killed by Tigran the Great, an Armenian king.
Vahan M. Kurkjian. "Chapter XXXIV - Armenian Mythology". A History of Armenia.