BT Ket 106a(8)var. Aruch :עבד תיבה ואיתותב בגויה‏ : he made a box and put himself in
See the entire entry for ytb vb. to sit ; to dwell; to stay, remain

BT Ket 106a(8) :עבד ^ת^יבותא ואתנחיה יתיב מר בתיבותא ומר אבראי וסיימוה‏ : he made a chest and set it down. He sat down in the chest and the other [i.e. Elijah] was outside it and explained it [i.e. Seder Eliyahu]
See the entire entry for tēḇō, tēḇōṯā n.f. chest; ark