出典:Wiktionary
From Middle English witter, witer, of North Germanic origin, from Old Norse vitr (“wise, knowing”), from Proto-Germanic *witraz (“knowing”), from Proto-Indo-European *weyd- (“to know”). Cognate with Icelandic vitur (“wise”). More at wit, wis.
witter (comparative more witter, superlative most witter)
From Middle English witteren, witeren, of North Germanic origin, from Old Norse vitra (“to make wise, make sure”), from Proto-Germanic *witrōną (“to make wise”), from Proto-Indo-European *weyd- (“to know”). Cognate with Icelandic vitra (“to make wise, make certain”), Icelandic vitur (“wise”). More at wit, wis.