A cufflink (also cuff link or cuff-link) is a decorative fastener worn by men or women to fasten the two sides of the cuff on a dress shirt or blouse.
Cufflinks are designed only for use with shirts which have buttonholes on both sides but no buttons. These may be either single or double-length (“French”) cuffs, and may be worn either “kissing,” with the ends pinched together, or “barrel-style,” with one end overlapping the other. Kissing cuffs are usually preferred.
Cufflink designs vary widely. The simplest design consists of a short post or chain connecting two disc-shaped parts. The part positioned on the most visible side is usually larger; a variety of designs can connect the smaller piece: It may be small enough to fit through the button hole like a button would; it may be separated and attached from the other side; or it may have a portion that swivels on the central post, aligning with the post while the link is threaded through the button-hole and swiveling into a position at right angles to the post when worn.
The visible part of a cufflink is often monogrammed or decorated in some way. There are numerous styles including novelty cufflinks, traditional cufflinks, contemporary cufflinks, utility cufflinks, and humorous cufflinks.