ぐてい 愚弟 LinksSentence search for 愚弟Sentence search for ぐていKanji details for 愚 and 弟Edit in JMdict Noun1. (one's) younger brotherHumble (kenjougo) languageNoun2. foolish younger brotherども、ぐてい愚弟がおせわになお世話になってるようで。Thanks, I hear you've been taking care of my little brat of a brother. Discussions Log in to talk about this word.