Definition from Wiktionary, the free dictionary
The first use of the term "site-swap" appears in the Summer 1991 Juggler's World article, "A Notation for Juggling Tricks" by Bruce (Boppo) Tiemann and Bengt Magnusson. The article states,
- If the juggler is thought of as juggling imaginary sites where the balls could be, as he does these tricks, which ball lands in which site is different from trick to trick. For this reason, we call these tricks "site-swaps." The number of sites is equal to the word length, and may be different from the number of balls actually being juggled. 
- (uncountable) A numerical notation used to describe juggling patterns, where each number represents the height and direction of a throw.
- (countable) A specific notation for a pattern.
- (uncountable sense): siteswap notation