An act of betrayal WordNet 3.0

A betrayal of one's principles principles, country, cause, etc. Open English WordNet

"Selling out", or "sold out" in the past tense, is a common expression for the compromising of a person's integrity, morality, authenticity, or principles by forgoing the long-term benefits of the collective or group in exchange for personal gain, such as money or power. Wikipedia

The compromising of principles in exchange for success Wikipedia Disambiguation

Act of compromising one's perceived principles for economic gain. Wikipedia Disambiguation

expression for the compromising of a person's integrity in exchange for personal gain Wikidata

A person who compromises his or her principles for financial gain. Wiktionary

A person who compromises his or her principles. Wiktionary (translation)