Reconstruction:Proto-Finnic/-us

From *-s. The *-u- may be generalized from derivatives or by confusion with *-uc, or both.^[1] The term may also derive more directly from Proto-Uralic *-wikse.^[2] Perhaps also more directly from *-u +‎ *-s.

*-us / *-üs

1. Forms some nouns from nominal stems.

• Finnish: -us
• Karelian:
  • North Karelian: -uš
  • South Karelian: -uš

From *-u +‎ *-s.^[1]

*-us / *-üs

1. Forms action/result nouns from verbs.

• Finnish: -us
• Karelian:
  • North Karelian: -uš
  • South Karelian: -uš