An implement for fastening buttons; a buttonhook. Also occasionally: a person who fastens the buttons of a garment. Frequently with modifying word, as "shoe-buttoner", "shirt-buttoner", etc. Now somewhat rare.

Something which fastens together, binds, or closes something tightly.

A person who makes or sells buttons.

A person who sews buttons on garments, especially as an occupation. Later also: a machine for sewing buttons on garments. Now somewhat rare.