What is the meaning of -aunce?

Forms nouns indicating states or processes, usually from verbs or other nouns; -ance.

Sandved, Arthur (1985), “9. Derivational Suffixes”, in Introduction to Chaucerian English (Chaucer Studies; 11), Part II: Morphology, Cambridge: D. S. Brewer, →ISBN, →OCLC, page 41.

-aunce, v.”, in MED Online, Ann Arbor, Mich.: University of Michigan, 2007.

Source: wiktionary.org