Translation guide
How to express switching allegiance, changing one's position in a conflict, or physically moving to the other side in Japanese.
To abandon one's group, team, or cause and join the opposing side.
Literally 'to turn over in sleep', this is the most common and natural way to say 'change sides' in the sense of betraying one's group and joining the enemy. Often used in historical, political, or competitive contexts.
He went over to the enemy side.
Just before the election, several lawmakers defected to the opposition party.
Means 'to betray'. It implies a breach of trust, not necessarily physically joining the other side, but often used when someone switches allegiance.
He betrayed his allies and leaked information to the enemy.
Literally 'to change saddles', this is a somewhat dated or literary expression for switching sides or changing one's affiliation, especially in politics or business.
He switched sides when the administration changed.
To go from one side of a physical space to the other.
To switch from supporting one argument to supporting the opposite argument.
Means 'to change one's position/stance'. Suitable for formal or informal contexts when someone shifts their viewpoint.
He changed his stance in the middle of the debate.
Literally 'to flip one's opinion', this implies a sudden or dramatic change of mind. Somewhat formal.
Do not translate 'change sides' literally as 側を変える (がわをかえる). This sounds unnatural and is not used for switching allegiance. Use 寝返る or 裏切る instead.
I want to go to the other side of the river.
The president suddenly changed his mind and opposed the plan.