A*dopt"er (&?;), n. 1. One who adopts.

2. (Chem.) A receiver, with two necks, opposite to each other, one of which admits the neck of a retort, and the other is joined to another receiver. It is used in distillations, to give more space to elastic vapors, to increase the length of the neck of a retort, or to unite two vessels whose openings have different diameters. [Written also adapter.]