Sauce bottle?

[Bufflehead]

Found this in spot filled with stuff from early 1900s-1940s. Is this an old sauce bottle? Has an interesting shape. Not totally round. Small embossed S on the bottom?

 

[Screwtop]

It looks like it might have been a Ketchup bottle.

 

[Patagoniandigger]

It's a sauce bottle to me. Very nice.

The top equals some other I have and they are all sauce bottles. (them all made in Argentina)
The one I show you is a local soda bottle that dates 1920's.
The part above the shoulder matches another parts of your bottle.
The designer combined shape elements to produce different designs.
According to the A in a circle embossed on the base it was made in the USA (American Glass Works)y

 

[Bufflehead]

As always very helpful. Thanks for all

 

[slugplate]

The lip design is very reminiscent of a ketchup.