The very original Calabash, is the Gourd Calabash, made with the gourd of dried a calabash. The bowl is usually made with meerschaum and it is removable for cleaning. The Gourd Calabash provide a very dry and fresh smoke.
Many pipemakers made interpretations of the Gourd Calabash but all in Briar.
I am used to consider a "Calabash" not only those pipes in this shape with removable bowl, but also those all-wood pieces made in this shape.
The solid wood interpretation of the calabash, with no removable bowl does not have the same characteristics of dry smoke.
The Calabash is usually 1/4 or full bent even if we could even find a straight versions.

CONNECTED SHAPES

The Bent Dublin has a bowl with the same shape of a sstraight Dublin but with bent shank.