A lace-up shoe with separate lacing tabs attached to the vamp.
Blucher has two uses, and both describe open lacing. In American usage it names the open-laced pattern itself: the Met describes the blucher, or “open tab”, as the pattern in which the lacing tabs are stitched on top of the vamp, against the closed-tab Oxford. Cheaney notes that the Derby is still commonly called a Blucher in the United States, where Blucher-type shoes are contrasted with Bal-type ones.
English shoemakers use the word more narrowly. Crockett & Jones lists “Whole Cut (Blucher)” as one of its Derby variations, beside toe-cap, apron, split-toe and brogue Derbies, so to such a maker a Blucher is one kind of Derby rather than every Derby. Either way the lacing is open, and the shoe suits wider feet with higher insteps. Cheaney traces the name to the Prussian field marshal Gebhard Leberecht von Blücher, whose military boot had two leather flaps laced together below the ankle.
In job listings
Blucher is seldom named in listings. It matters most in footwear product development and technical design, where a style’s pattern has to be specified exactly and an American and an English maker may mean different shoes by the same word. See current footwear development roles.