[er.rat.ic] adj [ME, fr. MF or L; MF erratique, fr. L erraticus, fr. erratus, pp. of errare] (14c) 1 a: having no fixed course: wandering "an ~ comet" b archaic: nomadic
2: transported from an original resting place esp. by a glacier "an ~ boulder" 3 a: characterized by lack of consistency, regularity, or uniformity b: deviating from what is ordinary or standard: eccentric "an ~ genius" syn see strange -- er.rat.i.cal adj -- er.rat.i.cal.ly adv -- er.rat.i.cism n
[2]erratic n (ca. 1623): one that is erratic; esp: an erratic boulder or block of rock