| 1 | Middle English | endelesly | For an infinite time; endlessly, timelessly,... |
| 2 | Old English | endelēaslīce | — |
| 3 | Old English | -līċe | — |
| 4 | Old English | -e | forming adverbs from adjectives; -ly |
| 5 | Old English | -en | mæġþ + API → mæġden; cocc + API → cycen, cicen;... |
| 6 | Old Norse | -inn | Used to create adjectives from nouns, meaning... |
| 7 | Proto-Norse | -īna- | — |
| 8 | Proto-Germanic | -īnaz | -en |
| 9 | Proto-Indo-European | -iHnos | Creates adjectives of materials |
| 10 | Proto-Indo-European | -no- | adjectival suffix |