As a noun, flannel is plausible-sounding rubbish, the kind of talk that sounds convincing but is really empty or self-serving. As a verb, to flannel someone is to soothe, flatter or charm them with smooth, insincere words, often to win them over or get something out of them. In current British usage the word also covers evasive talk of any sort: using a lot of words to avoid telling the truth or answering a question directly, rather than facing it head on.
What’s the origin of the phrase ‘flannel’?
The word begins as the name of the soft woollen fabric, and even that origin is uncertain. Dictionaries trace flannel either to the Welsh gwlanen, meaning a woollen article, or to the Old French flaine, a kind of coarse wool or blanket. The slang senses are usually explained as a metaphorical extension of the fabric’s own soft, smooth texture, transferred onto talk that has the same qualities: smooth, comforting and not entirely genuine.
Collins’ Dictionary of Slang dates the noun sense, meaning rubbish, albeit plausible rubbish, to the 1920s. The verb followed in the 1940s, when, according to the same source, to flannel came to mean talking nonsense in a soothing, plausible manner, especially for the purpose of charming a woman one wished to seduce. Green’s Dictionary of Slang gives a similar definition, describing the verb as flattering someone or currying favour through soothing, plausible talk used to the same end.
Green’s Dictionary of Slang also records an alternative, unconfirmed theory for the noun: that it grew out of nineteenth-century tradesmen’s jargon for the ornate, scroll-ridden letterheads with which shopkeepers decorated the invoices they sent to their aristocratic clients, the elaborate flourishes standing for empty show rather than substance. This account has never been confirmed and sits alongside the fabric explanation rather than replacing it.
It is worth keeping flannel separate from the American compound flannel mouth, which describes an Irishman or, more generally, a loudmouth or braggart who talks too much and with too little sense. Despite the shared word, this is a distinct term with its own history, not simply an American version of the British flannel meaning nonsense.