Language is not a static thing; it changes and evolves based on what things remain part of a culture and what things leave that culture behind. Also, it's entirely possible for meanings to be lost and obscured over time. As a for instance people often use the words witch, wizard, warlock, magus, occultist, and sorcerer as if they were interchangeable terms that all meant the same thing (this also happens with the words devil and demon, but more on why those are different creatures here). Each of these terms evolved in a very specific way, and they're unique to the cultures that birthed them.
So let me tell you why the sorcerer is different from all of the others.
What Sorcery Is This?
Sorcerer is derived from the Old French word sorcier. This word came about right around the 1300s, and it referred to anyone who committed acts of a magical or supernatural nature.
All in all that description seems like pretty straightforward stuff, but if you track it back further things get interesting. You see sorcier is traced back to the Latin sortiarius, which means one who tells fortunes. It also refers to a person who quite literally influences the fates. In this way a sortiarus is someone who can either bring you good fortune, or someone who can make bad things happen to you if she so desires.
What Do You Mean "She"?
While we're used to thinking of sorcerers as male, the term sorceress was the first. In fact the female version showed up about 200 years before the male one did in the early 1500s. While it might seem like just a quirk of the language there's another explanation for it.
Roman mythology, like Greek mythology before it, believed that female figures held immense power over fate. This is why oracles were often women, and why goddesses were held in particularly high regard. Even figures like the three fates who spun and cut the threads of people's lives were female. This power wasn't just reserved for the clergy, or for mythological figures though; it bled its way into the culture, into ideas, and even as we see into the language that was used to describe the world.
What About The Other Names?
There are a ridiculous number of terms that we use to describe people who use magic. In addition to the sorcerer, check out the history and etymology of the warlock!