1. forming nouns denoting a quality or state or an instance of one: allegiance | extravagance | perseverance.

質、状態、実証を示す名詞を作る

2 forming nouns denoting an action: appearance | utterance.

行動を示す名詞を作る

from French -ance, from Latin -antia, -entia (from present participial stems -ant-, -ent-).