| offener Ringschlüssel | flare-nut wrench |
| öffentlicher Schlüssel | public key |
| Generalschlüssel | master key passe-partout passkey |
| vom Gegner eingeschlossen | beleaguered |
| Tenorschlüssel | tenor clef |
| Zentralschlüssel | master key |
| Datenbankschlüssel | database key |
| privater Schlüssel | private key |
| Ringschluss | cyclization |
| Wohnungsschlüssel | key |
| Fremdschlüssel | foreign key |
| Funkschlüssel | fob |
| Innensechskantschlüssel | Allen key |
| Violinschlüssel | G clef |
| Drehmomentschlüssel | torque wrench |
| Meeranschluss | access to the sea |
| Notenschlüssel | clef |
| Zimmerschlüssel | room key |
| Zweitschlüssel | spare key |
| offene Linie | open file |