Bui

Old Norse: Búi
Meaning: "Dwelling-Owner"

1. son of Karl
2. a Berserker
3. a warrior

1. Bui was the son of Karl ("Yeoman") and Snör ("Daughter-in-Law").

Poetic Edda: Rigsthula - The Song of Rig.

2.
The other Bui was a Berserker ("bear-shirt"), son of Arngrim and Eyfura. He was born in Bolm.

He was one of the Berserkers listed in the Poetic Edda: Hyndluljoth - The Poem of Hyndla

3.
There was also a Bui in the Prose Edda, he was a warrior or maybe the Berserk of the Poetic Edda.

"Thus sang Einarr Tinkling-Scale:

Helm-folded strife-bold Búi,--
Who from the south went forth
Into Gunn's Crash,--and din-swift
Sigvaldi offered battle."

Prose Edda: Skáldskaparmál LXI