catgut scraper

A humorous, slightly affectionate old-school insult for a fiddle player — or any string musician if you're feeling uncharitable. The joke plays on the historical fact that violin strings were once made from dried animal intestines (often sheep gut, not actually cat). The term carries a teasing, good-natured energy, more likely to be used as a winking joke among musicians than as a genuine dig. You won't hear it much today, but it's the kind of phrase that makes you smile when you do.