| 1 | Danish | Olsen | — |
| 2 | Danish | Ole | — |
| 3 | Danish | Olaf | — |
| 4 | Old Norse | Óláfr | — |
| 5 | Proto-Norse | ᚨᚾᚢᛚᚨᛁᛒᚨᛉ | — |
| 6 | Proto-Germanic | anulaibaz | — |
| 7 | Proto-Germanic | laibō | what is left, remainder, remnant |
| 8 | Proto-Indo-European | leyp- | to stick; fat or sticky substance |
| 9 | Proto-Indo-European | lēy- | to leave, let; to want, desire; to let; leave... |