It refers to a furniture style in vogue in late 1700's to early 1800's that featured graceful feet arched outward on both tables and sofas.

A Scottish born furniture designer and US cabinet-maker (1768-1854). Furniture style popular in the American Federal period (late 18th to mid-19th century), also called Federal Style, characterized by feet with a graceful outward curve on both tables and sofas. Seating pieces often have lyre-shaped backs, rolled top rails and arms.

Pertaining to or resembling the furniture made by Duncan Phyfe, especially the earlier pieces in the Sheraton & Directoire styles.