1) French word used in English 2) Infidelity 3) Lack of loyalty 4) Perfidy 5) The quality of being disloyal 6) Treachery 7) Unfaithfulness Found on https://www.crosswordclues.com/clue/disloyalty
Dis·loy'al·ty noun [ Prefix dis- + loyalty : confer Old French desloiauté , deslealté , French déloyauté .] Want of loyalty; lack of fidelity; violation of allegiance. Found on http://www.encyclo.co.uk/webster/D/87
the quality of being disloyal; lack of loyalty; unfaithfulness. · violation of allegiance or duty, as to a government. · a disloyal act. Found on https://www.infoplease.com/dictionary/disloyalty