Volleyball, basketball and baseball refer to the name of the sport itself as well as to the medium used in playing the games.
Soccer ball, on the other hand, is the ball used in playing the sport and "soccer" is a stand alone term pertaining to the game. But on a side note, volleyball was originally spelled as two words.
And unlike volleyball, basketball and baseball that readily share an idea on how they are possibly played, the word “soccer,” which is believed to have originated in Britain, has quite an intriguing origin.
Soccer comes from the official name of the sport, “association football.”
In the 1860s, as in most of history- with records as far back as 1004 B.C.- there were quite a lot of “football” sports in existence being played popularly throughout the world and of course, England.
Many of these sports had similar rules and eventually, on October 26th, 1863, a group of teams in England decided to get together and create a standard set of rules which would be used at all their matches. They formed the rules for “Association Football”, with the “Association” distinguishing it from the many other types of football sports in existence in England, such as “Rugby Football”.
Now British school boys of the day liked to nickname everything, which is still somewhat common. They also liked to add the ending “er” to these nicknames. Thus Rugby was, at that time, popularly called “Rugger”. Association Football was then much better known as “Assoccer”, which quickly just became “Soccer” and sometimes “Soccer Football”.
Know more about the origin of the word "soccer" on Todayifoundout.com.