Gooseberry

To play gooseberry in the sense of being a superfluous or unwanted third person dates from the early 19th century when gooseberry was a term for a chaperone. Either it derives from chaperones busying themselves picking gooseberries while the couple being chaperoned did whatever they wanted to, or from couples wanting to be alone would do so under the pretence of going gooseberry picking. Before this, from the early 1700s, gooseberry was a synonym for a foolish or stupid person, while in Shakespeare’s time a gooseberry was thought of as a worthless trifle, Henry IV Part II, Act I, Scene II, “not worth a gooseberry”.