Last name Washa (Wash 
, Washa 
) , around the globe, is quite a common family name. The cognomen Washa is characteristic of Tanzania, where it is quite a rare surname, Trinidad and Tobago, and Bahrain, where it is a rare surname. Measured by absolute frequency, this name is the most popular in the United States, Tanzania, and Nigeria. Much less frequently, Washa is the forename as well as the last name.