Turbulent, a.
Etymology: [L. turbulentus, fr. turba disorder, tumult: cf. F. turbulent. See Turbid.]
1. Disturbed; agitated; tumultuous; roused to violent commotion; as, the turbulent ocean. Calm region once, And full of peace, now tossed and turbulent. Milton.
2. Disposed to insubordination and disorder; restless; unquiet; refractory; as, turbulent spirits. Sagacious, bold, and turbulent of wit. Dryden.
3. Producing commotion; disturbing; exciting. Whose heads that turbulent liquor fills with fumes. Milton.
Syn. -- Disturbed; agitated; tumultuous; riotous; seditious; insubordinate; refractory; unquiet.
Shades of meaning
Fernald lists turbulent only as an antonym, under calm.
He lists it without comment; the entries above explain its neighbors.