Agitate, v. t. [imp. & p. p. Agitated; p. pr. & vb. n. Agitating.] — Webster enters it under “agitate”
Etymology: [L. agitatus, p. p. of agitare to put in motion, fr. agere to move: cf. F. agiter. See Act, Agent.]
1. To move with a violent, irregular action; as, the wind agitates the sea; to agitate water in a vessel. "Winds . . . agitate the air." Cowper.
2. To move or actuate. [R.] Thomson.
3. To stir up; to disturb or excite; to perturb; as, he was greatly agitated. The mind of man is agitated by various passions. Johnson.
4. To discuss with great earnestness; to debate; as, a controversy hotly agitated. Boyle.
2 more senses
5. To revolve in the mind, or view in all its aspects; to contrive busily; to devise; to plot; as, politicians agitate desperate designs.
Syn. -- To move; shake; excite; rouse; disturb; distract; revolve; discuss; debate; canvass.
Shades of meaning
Fernald lists agitated only as an antonym, under calm.
Where he writes about it:
To agitate in its literal use is nearly the same as to shake, tho we speak of the sea as agitated when we could not say it is shaken; the Latin agitate is preferred in scientific or technical use to the Saxon shake, and especially as applied to the action of mechanical contrivances; in the metaphorical use agitate is more transitory and superficial, shake more fundamental and enduring; a person's feelings are agitated by distressing news; his courage, his faith, his credit, or his testimony is shaken. — from shake