Synonyms of the word 
UNPRINCIPLED → DISHONORABLE - DISHONOURABLE - IMMORAL - UNSCRUPULOUS
unprincipled
- adj. lacking moral values.
dishonorable
- adj. Without honor, or causing dishonor.
- adj. Lacking respect or ethical principles.
dishonourable
- adj. Alternative spelling of dishonorable.
immoral
- adj. Not moral; inconsistent with rectitude, purity, or good morals; contrary to conscience or the divine law.
unscrupulous
- adj. Without scruples; immoral.
- adj. Contemptuous of what is right or honorable.
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