Cheval-de-frise n. (pl. chevaux-de-frise) (commonly used in the plural) (Mil.) A piece of timber or an iron barrel traversed with iron-pointed spikes or spears, five or six feet long, used to defend a passage, stop a breach, or impede the advance of cavalry, etc. "Obstructions of chain, boom, and cheval-de-frise."
Collaborative International Dictionary of English 0.48