articulate

Where it comes from

Articulate came from Late Latin articulatus, clearly uttered, the participle of articulare, to make distinct sounds and, earlier, to divide into parts. That verb came from Latin articulus, a small joint or distinct part, itself a diminutive of artus, joint.

How the meaning developed

A joint both separates parts and connects them into a working whole. The same image was applied to speech divided into distinct, intelligible sounds; an articulate speaker then became someone able to arrange and express thoughts clearly.