Jonathon is a variant spelling of Jonathan, from the Hebrew Yehonatan, which means "God has given". In the Bible Jonathan is the son of King Saul and the loyal friend of David. The spelling with an o was most common in the 1980s and 1990s; it ranked number 226 in 2000, fell out of the top 1000 in 2017 and stands at number 1488 in 2025.