French knickers (also called tap pants in the United States (US)) are a type of women's underwear or lingerie. The term is predominantly used in the United Kingdom (UK) and Australia to describe a style of underpant that is similar in look to a pair of shorts. French knickers are worn from the hip, concealing some of the upper thigh and all of the buttocks. The garment features an "open leg" style (a loose fitting leg opening without elastic cuffs) that allows for a more comfortable fit and the straight-cut leg cuffs can be designed with or without trimming. The fabric is often "bias cut".

French knickers are not to be confused with other underpant styles like "hipsters", "briefs", "bikini bottoms" and "boyshorts", all of which feature elasticated leg openings and fit more snuggly to the body.

French knickers are ideally accompanied by full, flared and A-Line skirts, trousers and dresses, as they can add bulk and produce a visible panty line (VPL). The item is an elegant, comfortable and healthier alternative to more fitted forms of underwear and luxury fabrics like silk are often used in their production.