There is, however, a still graver and quite insuperable distinction between the parallactic path and the aberrational path.
1590s, "a wandering, straying," from Latin aberrationem (nominative aberratio) "a wandering," noun of action from past participle stem of aberrare "to wander out of the way, lose the way, go astray," from ab- "away" (see ab-) + errare "to wander" (see err). Meaning "deviation from the normal type" first attested 1846.
aberration ab·er·ra·tion (āb'ə-rā'shən)
A departure from the normal or typical.
A psychological disorder or abnormal alteration in one's mental state.
A defect of focus, such as blurring in an image.
An imperfect image caused by a physical defect in an optical element, as in a lens.
A deviation in the normal genetic structure or number of chromosomes in an organism.