口頭

1. Origins, structure, and basic meaning

• Structure: 口頭 (こうとう) means communication by speech rather than writing. It appears as a rejected contrast and an adopted means.
• Basic usage: Changes must be written rather than oral; a staff member gives a brief spoken explanation.

2. Common pitfalls and similar expressions

• Oral method rejected and spoken explanation received
  • 口頭ではなく excludes a medium; 口頭で selects it. The word concerns delivery mode, not the content's formality.