disorder · chaos

1. Origins, structure, and basic meaning

• Structure: 乱 expresses a disturbance of order or arrangement. 乱れる and 乱す are different verb forms.
• Basic usage: It can describe disrupted sleep schedules or order in a queue, as well as visible things such as messy hair.

2. Common pitfalls and similar expressions

• Becoming disordered and causing disorder
  • 髪が乱れる describes hair becoming messy; 風が髪を乱す describes wind messing it up.
  • 乱れる is みだれる, and 乱す is みだす. A transitive verb does not necessarily describe a deliberate human action.
• The scope of confusion
  • 混乱, read こんらん, covers disorder in a situation and confusion in thought or understanding.
  • 混乱 caused by an explanation need not involve physical objects being scattered.