noun

a slit made in a garment to receive a button for fastening.

verb

attract the attention of and detain (someone) in conversation, typically against their will.

reporters buttonhole officials coming out of the press secretary’s office

accost,speak to,talk to,call to,shout to,hail,initiate a discussion with,address,approach,waylay,take aside,detain,stop,halt,grab,catch,confront,importune,solicit,collar,nobble