| 1 | English | fact | Something actual as opposed to invented;... |
| 2 | English | factness | The quality of being based on facts; The quality... |
| 3 | English | -ness | Appended to adjectives to form nouns meaning "the... |
| 4 | Middle English | -nesse | Affixed to adjectives to form abstract nouns... |
| 5 | Old English | -nes | Used to form abstract nouns, usually from... |
| 6 | Proto-West Germanic | -nassī | Used to form abstract nouns, usually from... |
| 7 | Proto-Germanic | -inassuz | -ness |
| 8 | Proto-West Germanic | -ī | -ness, -th |
| 9 | Proto-Germanic | -į̄ | -th |
| 10 | Proto-Indo-European | -íh₂ | — |
| 11 | Proto-Indo-European | -h₂ | Creates collective nouns, which refer to groups... |