| Subject | English | German |
| med. | Flack node | Keith-und-Flack-Knoten (nodus sinuatrialis) |
| med. | Flack node | Flack-Knoten (nodus sinuatrialis) |
| med. | Flack node | SA-Knoten (nodus sinuatrialis) |
| med. | Flack node | Sinuatrialknoten (nodus sinuatrialis) |
| med. | Flack test | Flack Pressversuch |
| med. | Flack test | Flack-Test |
| med. | Flack test | Flack Kreislaufprobe |
| mining. | flack wick | Flachdocht (einer Wetterlampe) |
| med. | Keith-Flack node | Flack-Knoten (nodus sinuatrialis) |
| med. | Keith-Flack node | SA-Knoten (nodus sinuatrialis) |
| med. | Keith-Flack node | Keith-und-Flack-Knoten (nodus sinuatrialis) |
| med. | Keith-Flack node | Sinuatrialknoten (nodus sinuatrialis) |
| med. | Keith-Flack node | Keith-Flackscher Knoten |
| med. | node of Keith and Flack | Keith-Flack-Knoten |
| med. | node of Keith and Flack | Nodus sinuauricularis |
| med. | node of Keith and Flack | Schrittmacher |
| med. | node of Keith and Flack | Sinusknoten |
| med. | node of Keith and Flack | Keith-Flack-Bündel |
| fig. | take a lot of flack | einiges an Kritik einstecken müssen |