I'm going to get back on track with my idea to keep up with a weekly series when I share the meaning behind some common expressions. As you can imagine some are not so straightforward and have some conflicting stories behind them. Many of these expressions originated hundreds of years ago.

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Son of Gun is used often to replace Son of a *itch(I'm sure I can probably say that here, but I don't like to cuss) and pretty much has the same use in conversation. You may use it affectionately with a friend or derogatorily if someone has upset you.

I would say this expressions has one main story behind it with some slight variations. I will start by presenting it the way I always remembered it.

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It can from a time of pirates and pirate hookers.

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Of course I'm sure these poor ladies on the pirate vessels may not have been there by choice and we don't need to debate the morale of the pirate. Anyways of course some of the women would become pregnant and be forced to give birth on these long voyages. Since there was not a lot of room and childbirth can get in the way of other pirate activities on board. These women would give birth in the cannon bays or whatever it's called. When it came time to sign the birth registries the father was usually unknown so the baby was recorded as "Son of a Gun". Thus it was originally a child with unknown fatherhood and born from a mother with poor morals (or a terrible situation).

Most of the other theories revolve around this but pirates replaced by any sailors and hookers replaced by wives that may have been unfaithful on these long voyages.

Further down the line is was said to be used to described the child born of any man serving in the military in any capacity. Thus the military man was serving the gun and the child was his son.

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I prefer the pirate version but the sailor one is pretty much the same. There are a few additional variations as well.

Another version claims that the ships guns were fired during the birthing process to help hasten the birth, while another theory claims that the cannons were fired to help initiate labor when women were at term. (crazy ways used to initiate or speed up labor could be another post of its own)

The final and most far fetched and thus unlikely origin of this expression was actually on the popular myth busters TV show and proved to be busted. There was a myth from the civil war that a man was shot thought his testicle then the bullet struck a woman and caused her to become pregnant.

Yeah right, just admit it, you cheated while you were gone away for the war.

Anyways hope you enjoyed another installment of the newly titles "Origin's of Expression Series"

If you want to read the first in the series here is the link

Blow Smoke up Your Ass