Agitator

1. n. An implement for shaking or mixing.
2. n. One who agitates; one who stirs up or excites others; as, political reformers and agitators.
3. n. One of a body of men appointed by the army, in Cromwell’s time, to look after their interests; — called also adjutators.

The word meanings were obtained from OPTED(The Online Plain Text English Dictionary), which is based on “The Project Gutenberg Etext of Webster’s Unabridged Dictionary” which is in turn based on the 1913 US Webster’s Unabridged Dictionary (See Project Gutenburg), as a text file.