Erratic, a.
Etymology: [L. erraticus, fr. errare to wander: cf. F. erratique. See Err.]
1. Having no certain course; roving about without a fixed destination; wandering; moving; -- hence, applied to the planets as distinguished from the fixed stars. The earth and each erratic world. Blackmore.
2. Deviating from a wise of the common course in opinion or conduct; eccentric; strange; queer; as, erratic conduct.
3. Irregular; changeable. "Erratic fever." Harvey. Erratic blocks, gravel, etc. (Geol.), masses of stone which have been transported from their original resting places by the agency of water, ice, or other causes. -- Erratic phenomena, the phenomena which relate to transported materials on the earth's surface.
1 other Webster entry under this spelling
Erratic, n.
1. One who deviates from common and accepted opinions; one who is eccentric or preserve in his intellectual character.
2. A rogue. [Obs.] Cockeram.
3. (Geol.)
Any stone or material that has been borne away from its original site by natural agencies; esp., a large block or fragment of rock; a bowlder.
Note: In the plural the term is applied especially to the loose gravel and stones on the earth's surface, including what is called drift.