Tubac is a census-designated place (CDP) in Santa Cruz County, Arizona, United States. The population was 1,191 at the 2010 census. The place name "Tubac" is an English borrowing from a Hispanicized form of the O'odham name, which translates into English as "rotten". The original O'odham name is written Cuwak. The first syllable is accented. When first taken into Spanish speech, it was spelled Tubaca. Finally over time the last "a" was dropped.