| illegal(wrong, immoral, unprincipled) |
| improper(wrong, immoral, unprincipled) |
| inconstant(fickle, untrustworthy, unprincipled) |
| lying(fickle, untrustworthy, unprincipled) |
| mercenary(wrong, immoral, unprincipled) |
| moonlighting(fickle, untrustworthy, unprincipled) |
| not true to(expression, idiom, fickle, untrustworthy, unprincipled) |
| of bad faith(expression, idiom, fickle, untrustworthy, unprincipled) |
| perfidious(fickle, untrustworthy, unprincipled) |
| perjurious(fickle, untrustworthy, unprincipled) |
| polygamous(fickle, untrustworthy, unprincipled) |
| quicksilver(fickle, untrustworthy, unprincipled) |
| reprobate(corrupt, dishonest, immoral) |
| scam(wrong, immoral, unprincipled, unethical) |
| secret(dishonest, cunning, deceitful, sneaky, underhanded) |
| sharp(wrong, immoral, unprincipled) |
| slick(wrong, immoral, unprincipled) |
| snake in grass(expression, idiom, fickle, untrustworthy, unprincipled) |
| sneaky(wrong, dishonest, immoral, cunning, deceitful) |
| stealthy(dishonest, cunning, deceitful, sneaky, underhanded) |