sittings is a form of:

Cheval-de-frise



noun — Plural: Chevaux-de-frise
1.
ចម្រឹងដែក ឬ ឈើបោះជាបន្លារាំងផ្លូវ
ENGLISH MEANING
noun — Plural: Chevaux-de-frise
1.
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.