Er‐rat″ic (?), a. [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.