Solfatara

Solfatara (Solfata`ra) , a fissure or crevice in the earth which emits sulphurous and other vapours, and in regions where volcanoes have ceased to be active; they are met with in South Italy, the Antilles, Mexico, and Java.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Soleure * Solferino
[wait for the fun]
Sokoto
Solano
Solar Cycle
Solar Myth
Solar Year
Soldan
Solecism
Solemn League and Covenant
Solent
Soleure
Solfata`ra
Solferino
Solidarity
Solidus
Solingen
Solomon
Solomon of England
Solomon of France
Solomon Islands
Solomon's Ring
Solon