Where does “-era” come from?

-era (Old Norse) comes from Middle High German -ieren, from Old French -ier, from Latin -ārius, from Proto-Italic *-āzios — Forms relational adjectives to nouns (and rarely numerals).

Ancestry of “-era”, step by step

Step	Language	Word	Meaning
1	Middle High German	-ieren	used in verbs, indicating the action of doing...
2	Old French	-ier	suffix used to form infinitives of first...
3	Latin	-ārius	er
4	Proto-Italic	*-āzios	Forms relational adjectives to nouns (and rarely numerals)

Words derived from “-era”

-ere
-ere

Every word from Proto-Italic *-āzios →Every word from Latin -ārius →Every word from Old French -ier →