the region of the United States lying to the west of the Mississippi River

of or characteristic of eastern regions of the United States

the region of the United States lying to the west of the Mississippi River

of a region of the United States generally including New Mexico; Arizona; Texas; California; and sometimes Nevada; Utah; Colorado

of a region of the United States generally including Ohio; Indiana; Illinois; Iowa; Missouri; Kansas; Nebraska; and sometimes Michigan; Wisconsin; Minnesota

of a region of the United States generally including Washington; Oregon; Idaho; and sometimes Montana; Wyoming

of a region of the United States usually including Colorado; Nevada; Utah