treason

Hacking your brother’s email account and sharing all his secrets with your mom could be considered an act of personal treason, meaning you have betrayed your brother.

The word treason can be traced back to the Latin word traditio(n-), which comes from the verb tradere meaning “to hand over, betray.” If you commit treason, that’s what you do: you betray. The word is typically used to refer to the betrayal of a government or a country, like when a spy shares national secrets with another country, but it can be used to refer to personal betrayals as well.

Definitions of treason
1

n a crime that undermines the offender's government

Synonyms:
high treason, lese majesty
Type of:
crime, criminal offence, criminal offense, law-breaking, offence, offense
(criminal law) an act punishable by law; usually considered an evil act

n disloyalty by virtue of subversive behavior

Synonyms:
subversiveness, traitorousness
Types:
betrayal
the quality of aiding an enemy
Type of:
disloyalty
the quality of being disloyal

n an act of deliberate betrayal

Synonyms:
betrayal, perfidy, treachery
Types:
double cross, double-crossing
an act of betrayal
sellout
an act of betrayal
Type of:
dishonesty, knavery
lack of honesty; acts of lying or cheating or stealing

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