Calma
From Tolkien Gateway
Calma is a noun meaning "lamp" in Quenya. . Compare with calar in Sindarin.
Calma is also the name of the 3rd letter of the Tengwar alphabet and is the first letter of the Calmatéma.
In Quenya and the Mode of Beleriand, it has the value of K.
In Westron and other languages, the letter is called Ché and its value is CH (as in church).