Where does the word “alone” come from and What does it mean?

One who is alone is distinctly “one,” not two or more. And that was the original intent and use of the word “alone”.

It was formed from all one, wholly one, and was used as two words until the fourteenth century. In those days and until about the end of the seventeenth century the word one was pronounced just as we pronounce “own” today.

This pronunciation survives in “only.” (See also ATONE.)