| Fiduz | confidence |
| fiduziell | fiducial |
| Fidel | fiddle vielle |
| fidel | jolly merry |
| Vaduz | Vaduz |
| RFID | RFID |
| Fidibus | spill |
| Fluidum | aura |
| Fideist | fideist |
| Fidschi | Fiji Fijian |
| fiduziarisch | fiduciary |
| Triduum | triduum |
| heiduck | hajduk |
| Ovidukt | Fallopian tube oviduct |
| Solidus | solidus |
| Duzen | T use |
| duzen | be on first-name terms |
| Fideismus | fideism |
| Konfidenz | confidence trust |
| Perfidie | perfidy |