wayward

American Heritage® Dictionary of the English Language, Fourth Edition

1. adj. Given to or marked by willful, often perverse deviation from what is desired, expected, or required in order to gratify one's own impulses or inclinations. See Synonyms at unruly.
2. adj. Swayed or prompted by caprice; unpredictable.

Century Dictionary and Cyclopedia

1. Full of caprices or whims; froward; perverse.
2. Irregular; vacillating; unsteady, undulating. or fluctuating: as, the wayward flight of certain birds.
3. Synonyms Wayward, Wilful, Contrary, Untoward, headstrong, intractable, unruly. The italicized words tend toward the same meaning by different ways. Wayward, by derivation, applies to one who turns away from what he is desired or expected to be or to do; but. from its seeming derivation, it has come to apply more often to one who turns toward ways that suit himself, whether or not they happen to be what others desire. Wilful suggests that the person is full of self-will, which asserts itself against those whose wishes ought to be deferred to or whose commands should be obeyed. Contrary and untoward express the same idea, the one in a positive, the other in a negative form. Contrary is an energetic word, expressing the idea that one takes, or is disposed to take, the course exactly opposite to that which he is expected or desired to take. Contrariness, when ingrained, becomes perverseness: as, a contrary disposition; a contrary fellow. This use of contrary is by many considered colloquial, but has the recommendation of figurative force. Contrary and untoward view the person as one to be managed; untoward views the person also as the object of mental or moral discipline: this perhaps through its use in Acts ii. 40. An untoward person is not responsive to persuasion, advice, influence, or requests; untoward circumstances are similarly such as do not help us in our plans. All these words imply that the only consistency in the person's conduct is in this self-willed independence of others' wishes or opposition to them, but untoward implies it least. See perverse.

Wiktionary

1. adj. given to wilful, perverse deviation from the expected norm; tending to stray
2. adj. obstinate, contrary and unpredictable
3. adj. sports not on target

GNU Webster's 1913

1. adj. Taking one's own way; disobedient; froward; perverse; willful.

WordNet 3.0

1. adj. resistant to guidance or discipline