Webster’s Revised Unabridged Dictionary · 1913
Deviate
De′vi·ate (·āt), v. i. [imp. & p. p. Deviated; p. pr. & vb. n. Deviating.] [L. deviare to deviate; de + viare to go, travel, via way. See Viaduct.] To go out of the way; to turn aside from a course or a method; to stray or go astray; to err; to digress; to diverge; to vary.
Thus Pegasus, a nearer way to take, May boldly deviate from the common track. Pope.
Syn. — To swerve; stray; wander; digress; depart; deflect; err.
De′vi·ate, v. t. To cause to deviate. [R.]
To deviate a needle. J. D. Forbes.