Where does “airgeadóir” come from?

airgeadóir (Irish) comes from Irish airgead, from Irish -óir, from Old Irish -óir, from Proto-Brythonic -ọr, from Latin -ārius, from Proto-Italic *-āzios — Forms relational adjectives to nouns (and rarely numerals).

airgeadóir (Irish): cashier; teller

Definitions

cashier; teller

Ancestry of “airgeadóir”, step by step

Step	Language	Word	Meaning
1	Irish	airgead	silver; money, sum of money
2	Irish	-óir	-er; suffix appended to words to create an agent...
3	Old Irish	-óir	er, -or
4	Proto-Brythonic	-ọr	—
5	Latin	-ārius	er
6	Proto-Italic	*-āzios	Forms relational adjectives to nouns (and rarely numerals)

Every word from Proto-Italic *-āzios →Every word from Latin -ārius →Every word from Irish -óir →