| 1 | Scots | cannae | cannot |
| 2 | Scots | can | can; be able to |
| 3 | Middle English | can | Alternative form of canne |
| 4 | Middle English | cunnen | To know about; To be able to; to have the... |
| 5 | Old English | cunnan | to know, to be familiar with; can, to know how |
| 6 | Proto-West Germanic | kunnan | to recognise; to know how, to be able |
| 7 | Proto-Germanic | kunnaną | to know, to be familiar with, to recognise; to... |
| 8 | Proto-Indo-European | ǵneh₃- | to know |