Excuse me, if it's a strange or stupid question, but I'm burning with curiosity. Once my brother asked me if I know an old English word expressing denial, but deriving not from Latin or Greek. He said that maybe it's a Celtic word. But it sounds not like "no" or "not" and has no relation to "un-", "in-","im-", "a-", "dis-", "mis-" and so on. He is not very good at English, but I know he doesn't use to talk nonsense. So I was really interested: is it true, and such word exists, or he's understood something wrong? I consulted a dictionary, but found nothing like it. Could anybody help me? I realize that European languages are from the same family, and denial sounds very alike in English, German, Franch, Italian, Spanish, Russian or in Latin, but... who knows ? Thank you.