High-principled is an adjective used to describe individuals who are honest and morally upright. Alternatively, low-principled refers to someone who lacks integrity or is deceitful. Other antonyms for high-principled include unprincipled, immoral or unethical which suggest a lack of adherence to principles or ethical standards. Dishonest, deceitful, corrupt, and fraudulent are also antonyms for high-principled. Those who are dishonest in their dealings and have a propensity to lie and cheat are considered low-principled. Therefore, high-principled individuals are the opposite of those who lack moral ethics or principles.