What does -ary mean?

-ary meaning in Etymology Dictionary

adjective and noun word-forming factor, normally from Latin -arius, -aria, -arium "associated with, regarding; the man involved with," from PIE relational adjective suffix *-yo- "of or belonging to." It appears in words lent from Latin in center English. In later on borrowings from Latin to French, it became -aire and passed into Middle English as -arie, consequently -ary.