| 1 | English | acidic | Having a pH less than 7, or being sour, or having... |
| 2 | English | acid | Sour, sharp, or biting to the taste; tart; having... |
| 3 | French | acide | acid, acidic, sour, tart; acid, acidic; acid |
| 4 | Latin | acidus | sour, tart, acid, bitter; harsh, grating, rough,... |
| 5 | Latin | aceō | — |
| 6 | Proto-Italic | akēō | be sharp-tasting, be sour |
| 7 | Proto-Indo-European | h₂eḱ-éh₁-ye-ti | — |
| 8 | Proto-Indo-European | h₂eḱ- | sharp |