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mid-14c., "to draw asunder or apart, to turn aside" (literal and figurative), from Latin distractus, past participle of distrahere "draw in different directions," from dis- "away" (see dis-) + trahere "to draw" (see tract (n.1)).
Sense of "to throw into a state of mind in which one knows not how to act" is from 1580s. Related: Distracted; distracting; distractedly; distractedness.