Aloha is a census-designated place and an unincorporated community in Washington County, Oregon, United States. According to the United States Census Bureau, the CDP has a total area of 7.4 square miles (19 Square Kilometer), all of it land. According to Oregon Geographic Names, the origin of the name Aloha is disputed. Some sources say it was named by Robert Caples, a railroad worker, but it is unknown why the name was chosen. Aloha post office was established in 1912. In 1983 Joseph H. Buck claimed that his uncle, the first postmaster, Julius Buck, named the office "Aloah" after a small resort on Lake Winnebago in Wisconsin. Supposedly the last two letters were transposed by the Post Office Department during the application process. The local pronunciation, however, has remained Ah-lowwa rather than Ah-lo-ha.