The word "Goodbye," first seen in the 16th century, comes from which phrase?

The practice of saying goodbye goes back centuries, with first evidence of the interjection found around 1565–75. It’s a contraction of the phrase “God be with ye.”

In those days, people didn’t have the means of communication we do today, and they often didn’t know when or if they would see that person again when they parted. So they issued a sincere send-off, asking God to be with them until they met again.

Over the years, the use of goodbye has become more cursory in many cases, and few people are likely invoking the help of God when they say it. In fact, most people don't even know the religious context when they say it. Variants on the word have also sprung up, further distorting its original significance

One widely used variant, which is significantly softer and a bit more infantile, is bye-bye. In fact, it was originally used in nurseries to help lull children to sleep. First evidence of the term can be found around 1700–10.