出典:Wiktionary
From Middle English quoth, quath, from 古期英語 cwæþ (first and third person past indicative of cweþan (“to say, speak to, address, exhort, admonish”)), from Proto-Germanic *kwaþ (first and third person past indicative of Proto-Germanic *kweþaną (“to say”)). Unrelated to quote.
quoth
quoth (三人称単数 現在形 quoths, 現在分詞 quothing, 過去形および過去分詞形 quothed)
「quoth」は動詞「quethe」の過去形、または過去分詞です