| ＪＭＴＲ | [ジェーエムティーアール, jie-emutei-a-ru] (n) Japan Material Test Reactor; JMTR |
| ＪＰＤＲ | [ジェーピーディーアール, jie-pi-dei-a-ru] (n) Japan Power Demonstration Reactor; JPDR |
| ＪＲ | [ジェーアール, jie-a-ru] (n) (See 日本国有鉄道) Japan Railways; JR; (P) |
| ＮＨＫ | [エヌエッチケー, enuecchike-] (n) (See 日本放送協会) Japan Broadcasting Corporation; Nihon Housou Kyoukai; NHK |
| ＰＬ教団 | [ピーエルきょうだん, pi-eru kyoudan] (n) (See パーフェクトリバティー教団) Church of Perfect Liberty (religious group founded in Japan in 1924) |
| アジャタ | [, ajata] (n) (abbr) (See 玉入れ) sport similar to ball-toss game played in schools (All Japan Tamaire) |
| イソハゼ | [, isohaze] (n) Eviota abax (species of pygmy goby ranging from Southern Japan to Hainan Is.) |
| イチモンジハゼ | [, ichimonjihaze] (n) Trimma grammistes (species of small goby found in Japan and Taiwan) |
| ええじゃないか | [, eejanaika] (exp) (1) isn't it great?; (n) (2) carnival-like religious celebrations (e.g. dancing festivals) that occurred across Japan from June 1867 to May 1868 |
| エリホシベニハゼ | [, erihoshibenihaze] (n) four-eye pygmy goby (Trimma hayashii, found from Japan to the Solomons) |
| オノコロ島;オノゴロ島;磤馭慮島(oK) | [オノコロじま(オノコロ島);オノゴロじま(オノゴロ島);おのころじま(磤馭慮島);おのごろじま(磤馭慮島), onokoro jima ( onokoro shima ); onogoro jima ( onogoro shima ); onokorojima ( ketsu] (n) (1) (arch) (See 天の瓊矛) Onokoro Island (in Japanese mythology, the island formed by drops of water falling from the heavenly jeweled spear); Onogoro Island; (2) Japan |
| オリエンタルバタフライフィッシュ;オリエンタル・バタフライ・フィッシュ | [, orientarubatafuraifisshu ; orientaru . batafurai . fisshu] (n) Oriental butterflyfish (Chaetodon auripes, species found mostly from Japan to Taiwan) |
| お雇い外国人;御雇外国人 | [おやといがいこくじん, oyatoigaikokujin] (n) hired foreigners; foreign advisors hired by the Japanese government for their specialized knowledge to assist in the modernization of Japan at the end of the Bakufu and during the Meiji Era |
| キリシタン版 | [キリシタンばん, kirishitan ban] (n) books printed in Japan by the Jesuits (1590-1612) |
| ココノホシギンザメ | [, kokonohoshiginzame] (n) Hydrolagus barbouri (species of cartilaginous fish found in the Sea of Japan and East China Sea) |
| ゴマテングハギモドキ | [, gomatenguhagimodoki] (n) spotted unicornfish (Naso maculatus, species of Pacific tang found from Japan and Lord Howe Island to Hawaii) |
| サンフランシスコ講和条約 | [サンフランシスコこうわじょうやく, sanfuranshisuko kouwajouyaku] (n) (See 対日講和条約) Treaty of San Francisco; Treaty of Peace with Japan (Sept. 8, 1951) |
| ジパング | [, jipangu] (n) Zipangu (the name for Japan used by Marco Polo) (ita |
| じゃぱゆき | [, japayuki] (n) derog. term for Asian women working in Japan |
| ジャパンファウンデーション | [, japanfaunde-shon] (n) Japan Foundation |
| ジャユプロ | [, jayupuro] (n) (abbr) Japan unique process |
| テンイバラザメ | [, ten'ibarazame] (n) straight-tooth weasel shark (Paragaleus tengi, species of Western Pacific weasel shark found from Japan to Viet Nam) |
| トモダチ作戦;友達作戦 | [トモダチさくせん(トモダチ作戦);ともだちさくせん(友達作戦), tomodachi sakusen ( tomodachi sakusen ); tomodachisakusen ( tomodachi sakusen )] (n) Operation Tomodachi; United States Armed Forces assistance operation to support Japan in disaster relief following the 2011 Tohoku earthquake and tsunami |
| トラザメ | [, torazame] (n) cloudy catshark (Scyliorhinus torazame, species found from Japan and Korea to Taiwan) |
| ナガヘラザメ | [, nagaherazame] (n) flathead catshark (Apristurus macrorhynchus, species from Japan and Taiwan) |
| ナミダクロハギ;ジャパンサージャンフィッシュ;ジャパンサージョンフィッシュ | [, namidakurohagi ; japansa-janfisshu ; japansa-jonfisshu] (n) Japan surgeonfish (Acanthurus japonicus, Indo-West Pacific species of tang found from Indonesia to the Philippines and Ryukyu Islands) |
| パーフェクトリバティー教団 | [パーフェクトリバティーきょうだん, pa-fekutoribatei-kyoudan] (n) Church of Perfect Liberty (religious group founded in Japan in 1924) |
| ハリストス正教会 | [ハリストスせいきょうかい, harisutosu seikyoukai] (n) (1) (See ハリストス) Eastern Orthodox Church; (2) Japan Orthodox Church |
| ヒメアオギハゼ | [, himeaogihaze] (n) wasp pygmy goby (Trimma flavatrum, species found from Japan to Australia) |
| フライ人 | [フライじん;フライジン, furai jin ; furaijin] (n) (sl) (from フライ+外人) (See フライ・2,外人) foreigner who fled Japan after the Mar. 11, 2011 Tohoku earthquake |
| ムラサキヌタウナギ | [, murasakinutaunagi] (n) Eptatretus okinoseanus (species of hagfish found in Japan and Taiwan) |
| ヤルタ秘密協定 | [ヤルタひみつきょうてい, yaruta himitsukyoutei] (n) (See ヤルタ会談) The Yalta Agreement (secret American-British-Soviet agreement wherein the Soviets agreed to attack Japan within three months of the German surrender |
| ゆうちょ銀行を除く;郵貯銀行を除く | [ゆうちょぎんこうをのぞく, yuuchoginkouwonozoku] (exp,v5k) excluding the Post Office bank; excluding Japan Post Bank |
| レコード大賞 | [レコードたいしょう, reko-do taishou] (n) (See 日本レコード大賞) the Japan Record Award |
| 三国一 | [さんごくいち, sangokuichi] (n) unparalleled in Japan and China and India (unparallelled) |
| 二七年テーゼ;２７年テーゼ | [にじゅうしちねんテーゼ, nijuushichinen te-ze] (n) 1927 Theses; Comintern policy documents regarding capitalism, imperialism, and a possible revolution in Japan |
| 五奉行 | [ごぶぎょう, gobugyou] (n) (See 五大老) the five commissioners (administrative organ of feudal Japan established by Toyotomi Hideyoshi) |
| 仁座鯛 | [にざだい;にざだひ;ニザダイ, nizadai ; nizadahi ; nizadai] (n) (uk) scalpel sawtail (Prionurus scalprum, species of tang found from Japan to Taiwan) |
| 伊弉冉尊;伊邪那美命 | [いざなみのみこと, izanaminomikoto] (n) (See 伊弉諾尊) Izanami; female deity who gave birth to Japan and the sun, moon, and storm gods |
| 伊弉諾尊;伊邪那岐命 | [いざなぎのみこと;いざなきのみこと, izanaginomikoto ; izanakinomikoto] (n) (See 伊弉冉尊) Izanagi; male deity who fathered Japan and the sun, moon, and storm gods |