What is a semite?
Semite comes from the name of the oldest son of Noah in the Hebrew Bible, Shem. Since neither Greek nor Latin have the “sh” sound, the name became “Sem.” “Semite” was used in linguistics to describe a person who is part of an ethnic, cultural or racial group who speak a Semitic language.
In the late 1800’s, there were a lot of “isms,” and “anti-isms.” For example, there was communism and anti-communism, socialism and anti-socialism. These are belief systems with which people agree or disagree. The idea of “anti-ism” was bastardized to describe negative political action against Jews. Jews were singled out as the only speakers of a Semitic language to be found worthy of the “anti-ism” label.
In 1879, the German journalist Wilhelm Marr wrote a pamphlet called “The Way to Victory of Germanicism over Judaism.” This pamphlet popularized the newly-coined term “antisemitism” to describe a new form of hostility towards Jews. Marrs’ followers founded the “League for Antisemitism.”
The German word is Antisemitismus. Though most English-language writers spell this word: “Anti-Semitism” with a hyphen, the original German word does not include a hyphen. Placing a hyphen between “anti” and “Semitism” implies that there is something called “Semitism,” which there is not.
After I read about the hyphen controversy in Peter Hays book, Why? Explaining the Holocaust, I decided to drop the hyphen and spell the word: “antisemitism.” Now this is a challenge because I use word to type and it keeps underlining “antisemitism,” trying to convince me that I am spelling it wrong. But I will persevere and continue to spell it sans hyphen.
I encourage you to do the same.
 Includes Hebrew, Arabic and Aramaic. See My Jewish Learning: Who are the Semites, by Bernard E. Lewis. http://www.myjewishlearning.com/article/who-are-the-semites/
 Hays, Peter. Why? Explaining the Holocaust at 5.