Wikiorðabók (Icelandic) comes from Icelandic orðabók, from Icelandic orð, from Old Norse orð, from Proto-Germanic wurdą, from Proto-Indo-European werdʰo-, from Proto-Indo-European werh₁- — to speak, say.
Wikiorðabók (Icelandic): Wiktionary project
Definitions
Wiktionary project
Ancestry of “Wikiorðabók”, step by step
Wikiorðabók traces back through two separate lines of ancestry.