clothing (side/shoulder buttoning jacket?)

Are you certain it's only on one side? Every uniform I've ever seen is symmetrical.

I assume you mean something similar to this. I don't know what it's called either. Maybe it's still called a double-breasted jacket.

Spaceship uniform!

Like others' said, it's a double breasted. It was interesting how the picture loaded without the head. I saw the coat and said, "Ok, an American Civil War Federal Infantry Dress Blues." Then I saw the face and thought, "Why is a woman wearing it? They didn't allow women in the infantry then."

Then I realised.

There's also the Mandarin or eastern style jacket that buttons up the left side. I don't think it's double breasted. Puma

Fencing jackets button or zip up one side. That side is OPPOSITE the sword arm. (So an attacking blade cannot enter the flap) Hence, a right handed fencer will have the buttons up the left side of the jacket.

There is no particular name for this style that I am aware of. "Plastron" is commonly used to denote protective body wear. "Tunic" is a generic word that covers everything from what we commonly refer to as a jacket or coat - to a heavy shirt.

AS others have noted, during the mid nineteenth century - uniforms that were double breasted, or 'double faced' had TWO rows of buttons. One side overlapped to button over the other, leaving the interior side as extra padding. This COULD be accomplished either left or right handed. Additionally, the button holes could be folded back, and buttoned UPON themeselves, revealing the facing (usually a different colored lining) and the waistcoat underneath. Think of Civil War Uniforms as well as the double faced uniforms of the 18th centuries.

(Yeah, I own WAAAY to many costumes)