The name Jameis is of American origin, derived from the combination of James and Willis, both popular names among African Americans during the early to mid-20th century. The name gained prominence in the late 20th century and has been a consistent choice among parents ever since. Jameis has also appeared as a surname, originating from Scotland, with its earliest known bearers being recorded there in the 17th century.
Jameis had a notable peak in popularity with 41 births in 2014, but has since seen a steady decline, with only 6 births each in 2019 and 2020, before slightly increasing to 7 in 2021 and remaining at 6 in 2022. Over the ten-year period from 2013 to 2022, there were a total of 152 births named Jameis.