Words which start with S and end X?

There aren't many common English words that start with "S" and end with "X". Here are a few possibilities:

* Sex - a noun referring to sexual activity or the biological distinction between males and females.

* Sphinx - a mythical creature with the head of a human and the body of a lion, known for posing riddles.

* Syntax - the arrangement of words and phrases to create well-formed sentences in a language.

Note: "Sex" is a common word but can be considered a sensitive topic. "Sphinx" and "Syntax" are more academic or literary terms.