Brenndan is of Irish origin, derived from the ancient name 'Brandán', which means 'little salmon'. This unique and distinctive name was popularized by St. Brendan the Navigator, a monk who explored the Atlantic Ocean in the 6th century. Brenndan is often spelled with two 'n's at the end, making it a variant of the more common Brendan.
"The name Brenndan saw a steady increase in popularity between 1995 and 1998, peaking at 12 births in 1997. However, it experienced a decline thereafter, with only five births recorded each in 2003 and 2004. Overall, there were 56 babies named Brenndan between 1995 and 2004."