What does Decatur mean?
Decatur \d(e)-ca-tur\ as a boys' name. Surname. There is a process called "decating" in the manufacture of cloth. Deca- in Greek means "ten", but might also mean "pure". Stephen Decatur was an early 19th-century naval hero. There are several American towns named for him.
Decatur is an uncommonly occurring given name for men but a very prominent surname for both adults and children (#25926 out of 150436, Top 17%). (2000 U.S. Census)
Shown below is the birth name popularity of Decatur for boys. Decatur has yet to be listed in the list so far. (Top 1000 Baby Names Records, 2014)