Confab

This abbreviation of confabulation dates from the late 17th/early 18th century, 1701, according to the OED. A confab or confabulation means a talk or discussion together, the latter full word dating from c.1613 but its abbreviation had become totally acceptable by 1701. To fabulate is to tell stories and the words fable and fabulous derive from the same Latin source fabula, a fable. Fabulous began to mean incredible or astonishing from the early 1600s.