noun
disturber of the peace; troublemaker; nuisance
A person who disrupts public order or causes trouble; a formal or legalistic term. Rare in everyday conversation.
警察はその撹乱者を逮捕した。
The police arrested the disturber of the peace.
彼は会議でいつも撹乱者になる。
He always becomes a troublemaker at meetings.
Compound of 撹乱 (かくらん, 'disturbance, disruption') + 者 (しゃ, 'person'). The exact historical derivation is uncertain, but the spelling is conventionally associated with the meaning of a person who causes disturbance.