floss/flɔs; ?@ flɔ:s; flɔs/ n[U]1 rough silk threads from the outside of a silkworm's cocoon （蚕茧外层的）粗丝.2 (also 'floss silk) spun (but not twisted) silk thread used for embroidery 刺绣用的丝线.
牛津英汉双解词典