Conch is a general term that is used to indicate a range of shells from a medium to a large size, usually with a large aperture and spire.
The term conch is known for its prominent use in the novel
Lord of the Flies by Nobel Prize winner
William Golding.
The word conch comes from the Latin word
concha (that in turn comes from Ancient Greek), which means "shellfish".
Conch has two different pronunciations that are both widely accepted. The first way to say conch, and more widely used is,
conk. This pronunciation of conch is widely, but not uniquely used in the US. The other pronunciation of conch is
conch, where the "ch" are pronounced as they phonetically appear. This pronunciation of conch can be often heard in the UK. However, neither of these ways to pronounce conch are strictly specific to American or British English.