a mountain range in the eastern United States extending from Quebec to the Gulf of Mexico; a historic barrier to early westward expansion of the United States
例句
用作名词 (n.)
Taking off from an Atlantic coast airport,the plane is soon flying over the gentle slopes of the Appalachian Mountains. 从大西洋海岸的机场起飞,飞机不久后将飞过阿巴拉契亚山脉平缓的山坡。