Antonyms of adj unprincipled

2 senses of unprincipled

Sense 1
unprincipled (vs. principled) -- (lacking principles or moral scruples; "freedom from coarse unprincipled calumny"- A.E.Stevenson)

principled (vs. unprincipled) -- (based on or manifesting objectively defined standards of rightness or morality; "principled pragmatism and unprincipled expediency"; "a principled person")
        => high-principled -- (having high principles)

Sense 2
unprincipled -- (having little or no integrity)

INDIRECT (VIA dishonorable) -> honorable, honourable -- (worthy of being honored; entitled to honor and respect; "an honorable man"; "led an honorable life"; "honorable service to his country")

Similarity of adj unprincipled

2 senses of unprincipled

Sense 1
unprincipled (vs. principled) -- (lacking principles or moral scruples; "freedom from coarse unprincipled calumny"- A.E.Stevenson)
          Also See-> unscrupulous#1

Sense 2
unprincipled -- (having little or no integrity)
       => dishonorable (vs. honorable), dishonourable -- (lacking honor or integrity; deserving dishonor; "dishonorable in thought and deed")