| 1 | English | bitter | Having an acrid taste; Harsh, piercing or... |
| 2 | English | -er | A person or thing that does an action indicated... |
| 3 | Middle English | -er | agentive suffix; agent noun suffix |
| 4 | Old French | -er | Alternative form of -ier, verbal suffix;... |
| 5 | Latin | -āre | — |
| 6 | Proto-Italic | -āō | Forms primarily denominative verbs |
| 7 | Proto-Indo-European | -eh₂yéti | Creates iterative/ frequentative/ intensive... |
| 8 | Proto-Indo-European | -yéti | Creates intransitive, often deponent,... |
| 9 | Proto-Indo-European | yé- | — |
| 10 | Chichewa | iye | he, she |