Origin of Phrases - S
Son of a gun
Meaning: Exclamation of disbelief.
Example: I'll be a son of a gun. I didn't think you could keep a job for more than six months.
Origin: Early warships had very cramped quarters. Sailors slept between the cannons because that was the only space available.
They sometimes had female company on board. Some ships actually carried prostitutes. Other times a sailor's wife would be allowed on board so that he would not have to leave the ship, and potentially desert.
In any case, many children were conceived between the cannons, or guns. Woman who gave birth on the ships typically also did so between the guns.
The male children were thus called "son of a gun".