'Orthodox' means orthodox in life as well as faith

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"orthodoxus est recte credens, et ut credit [recte] vivens."

The orthodox man is [the one who is] believing rightly, and, as he believes, living [rightly, too].

     St. Isidore of Seville (c. 560-636) in Etymologies 8.14.5.  Latin ed. (with the interpolation of that second recte) Lindsay, vol. 1 (1911), n.p. (there are more recent critical editions).  Cf. PL 82, col. 294, which leaves that second recte out.  M. Sesan, "'Orthodoxie': histoire d’un mot et de sa signification," Istina 15, no. 4 (1970):  428 (425-434), cites PL 82, col. 388, but that is wrong.  The whole of sub-section 5 as trans. Barney, Lewis, Beech, & Berghof (Cambridge University Press) in 2006:

An 'orthodox person' (orthodoxus) is one who believes rightfully, and who lives [righteously] as he believes.  Now ὀρθῶς in Greek means 'rightly' (recte), δόξα is 'good repute' (gloria):  an orthodox person is a man 'of good and right repute' (recta gloria).  He who lives otherwise than as he believes cannot be called by this name.

And St. Isidore is right, both on the etymology (OED), and on the senses of δόξα; which, according to LSJ, can mean both opinion and repute.