苦い

Japanese

From Early Middle Japanese adjective 苦(にが)し (nigashi), with the 終(しゅう)止(し)形(けい) (shūshikei, “predicative form”) ending in し (shi) first replaced with the 連(れん)体(たい)形(けい) (rentaikei, “attributive form”) ending in き (ki), and then with the medial /-k-/ falling out to result in an ending of い (i). Ultimately from Proto-Japonic *ninka; cognate with Proto-Ryukyuan *niga.

First cited to a text from 858.^[1]

Plain	苦い	にがい	`[nìgáꜜì]`
Conjunctive	苦くて	にがくてにがくて	`[nìgáꜜkùtè]` `[níꜜgàkùtè]`
Continuative	苦く	にがくにがく	`[nìgáꜜkù]` `[níꜜgàkù]`
Negative	苦くない	にがく・ないにがく・ない	`[nìgáꜜkù náꜜì]` `[níꜜgàkù náꜜì]`
Past	苦かった	にがかったにがかった	`[nìgáꜜkàttà]` `[níꜜgàkàttà]`
Negative past	苦くなかった	にがく・なかったにがく・なかった	`[nìgáꜜkù náꜜkàttà]` `[níꜜgàkù náꜜkàttà]`
Conditional	苦ければ	にがければにがければ	`[nìgáꜜkèrèbà]` `[níꜜgàkèrèbà]`
Terminal	苦い	にがい	`[nìgáꜜì]`
Formal	苦いです	にがいです	`[nìgáꜜì dèsù]`

苦(にが)い • (nigai) -i (adverbial 苦(にが)く (nigaku))

bitter (flavor)
Antonym: 甘(あま)い (amai, “sweet”)

苦(にが)いコーヒー ― nigai kōhī ― bitter coffee
bitter (unpleasant)
苦(にが)い経験(けいけん) ― nigai keiken ― bitter experience

Classical conjugation of "苦し" (ク活用, see Appendix:Japanese verbs.)
Stem forms
Irrealis (未然形)	苦く^[1] 苦から^[2]	にがくにがから	nigaku nigakara
Continuative (連用形)	苦く^[1] 苦かり^[2]	にがくにがかり	nigaku nigakari
Terminal (終止形)	苦し	にがし	nigasi
Attributive (連体形)	苦き苦かる	にがきにがかる	nigaki nigakaru
Realis (已然形)	苦けれ	にがけれ	nigakere
Imperative (命令形)	苦かれ	にがかれ	nigakare
Key constructions
Negative	苦からず	にがからず	nigakarazu
Contrasting conjunction	苦けれど	にがけれど	nigakeredo
Causal conjunction	苦ければ	にがければ	nigakereba
Conditional conjunction	苦くば	にがくば	nigakuba
Past tense (firsthand knowledge)	苦かりき	にがかりき	nigakariki
Past tense (secondhand knowledge)	苦かりけり	にがかりけり	nigakarikeri
Adverbial	苦く	にがく	nigaku

^[1]Without auxiliary verb.
^[2]With auxiliary verb.

^ “苦”, in 日本国語大辞典 [Nihon Kokugo Daijiten]‎^[1] (in Japanese), concise edition, Tokyo: Shogakukan, 2006
^ Matsumura, Akira, editor (2006), 大辞林 [Daijirin] (in Japanese), Third edition, Tokyo: Sanseidō, →ISBN
^ NHK Broadcasting Culture Research Institute, editor (1998), NHK日本語発音アクセント辞典 [NHK Japanese Pronunciation Accent Dictionary] (in Japanese), Tokyo: NHK Publishing, Inc., →ISBN
^ Kindaichi, Kyōsuke et al., editors (1997), 新明解国語辞典 [Shin Meikai Kokugo Jiten] (in Japanese), Fifth edition, Tokyo: Sanseidō, →ISBN

“苦い”, in 漢字ぺディア [Kanjipedia]‎^[2] (in Japanese), The Japan Kanji Aptitude Testing Foundation, 2015–2026

Basic tastes in Japanese · 味覚(みかく) (mikaku) (layout · text)

甘(あま)い (amai)	酸(す)っぱい (suppai)	塩(しょ)っぱい (shoppai)	苦(にが)い (nigai)	辛(から)い (karai)	旨味(うまみ) (umami)