This star is also known as Deneb Kaitos, Difda, Difda al Thani, or Rana Secunda.
The name Deneb Kaitos derives from the Arabic Al Dhanab al Kaitos al Janubiyy, "The Tail of the Whale Towards the South."
The names Diphda, Difda and Difda al Thani come from the Arabic name Al Difdi` al Thani meaning "The Second Frog."
Rana Secunda is a Latin translation of Al Difdi` al Thani.
For the Arabs Diphda was the Second Frog with Fomalhaut as the First Frog.