| Subject | English | Japanese |
| tech. | phase boundaries | 相界 (sōkai) |
| phys. | phase boundary | 相界 (sōkai) |
| gen. | phase boundary potential | 相界電位 |
| gen. | phase boundary potential | 相関電位 |
| gen. | phase boundary potential | 界面電位 (kaimen-den'i) |
| phys. | phase-boundary potential | 界面電位 (kaimen-den'i) |