source follower

An output circuit whose output load is connected in the source circuit of a field-effect transistor and whose input is applied between the gate and the remote end of the source load, which may be at ground potential.

NOTE The term "source follower" as applied to linear circuits, usually refers to passive-pulldown or passive-pullup (bipolar) outputs; as applied to logic circuits, to open-source (unipolar) outputs.

References: 

JESD99B, 5/07