A broad sash, especially one that is pleated lengthwise and worn as an article of formal dress, as around a man's waist together with a tuxedo or dinner jacket.
stickpin
noun
An ornamented pin used to secure a necktie's end flat against the shirt, a tie tack.
How often have the words cummerbund and stickpin occurred in a corpus of books? (source: Google Ngram Viewer )