The Collaborative International Dictionary
Bois durci
Bois durci \Bois" dur`ci"\ [F., hardened wood.] A hard, highly polishable composition, made of fine sawdust from hard wood (as rosewood) mixed with blood, and pressed.
Wiktionary
bois durci
n. A hard, polishable composition of fine sawdust and blood, formerly used for making household items.