| Clue | Source | Date |
|---|---|---|
| Close-mouthed sound of agreement | New York Times Mini | 27 Oct 2025 |
| Vowelless agreement | Wall Street Journal | 25 Mar 2025 |
| "Yes" said without opening the mouth | Wall Street Journal | 21 Feb 2024 |
| Vowelless 'yes' | New York Times | 18 Apr 2021 |
| Vowelless utterance of affirmation |