| 55 | A Guide To Reading and Writing Japanese (Florence Sakade) |
| 94 | A Guide To Reading and Writing Japanese 3rd edition (Henshall, Seeley and De Groot) |
| 88 | A Guide To Remembering Japanese Characters (Kenneth G. Henshall) |
| 158 | A New Dictionary of Kanji Usage |
| 2553 | Classic Nelson (Andrew Nelson) |
| 99 | Essential Kanji (P.G. O’Neill) |
| 211 | Japanese Kanji Flashcards (Max Hodges and Tomoko Okazaki) |
| 1071 | Japanese Names (P.G. O’Neill) |
| 3.14 | Japanese for Busy People |
| 117 | Kanji and Kana (Spahn and Hadamitzky) |
| 117 | Kanji and Kana, 2nd Edition (Spahn and Hadamitzky) |
| 454 | Kanji in Context (Nishiguchi and Kono) |
| 1184 | Kodansha Compact Kanji Guide |
| 459 | Kodansha Kanji Dictionary (Jack Halpern) |
| 284 | Kodansha Kanji Learner’s Dictionary (Jack Halpern) |
| 344 | Kodansha Kanji Learner’s Dictionary, 2nd Edition (Jack Halpern) |
| 471 | Les Kanjis dans la tete (Yves Maniette) |
| 17450 | Morohashi |
| 384 | New Japanese English Character Dictionary (Jack Halpern) |
| 3133 | New Nelson (John Haig) |
| 461 | Remembering The Kanji (James Heisig) |
| 500 | Remembering The Kanji, 6th edition (James Heisig) |
| 206 | The Kanji Way to Japanese Language Power (Dale Crowley) |
| 171 | Tuttle Kanji Cards (Alexander Kask) |
Jōyō kanji, taught in grade 2
JLPT level N4
200 of 2500 most used kanji in newspapers
Stroke order
On reading compounds
- 海運 【カイウン】 maritime transport, shipping
- 海域 【カイイキ】 area of ocean
- 公海 【コウカイ】 high seas, international waters
- 内海 【ナイカイ】 inland sea, inlet, gulf, bay, lake
Kun reading compounds
- 海 【うみ】 sea, ocean, waters
- 海辺 【うみべ】 beach, seashore, seaside, coast
- 内海 【ないかい】 inland sea, inlet, gulf, bay, lake
- 血の海 【ちのうみ】 sea of blood, pool of blood
Readings
- Japanese names:
- あ、 あま、 うな、 うん、 え、 か、 た、 ひろ、 ひろし、 ぶ、 まち、 まま、 み、 め、 わたる
- Korean:
- hae
Spanish
- mar
- océano
- playa
Portuguese
- oceano
- mar
French
- mer
- océan
| 347 | 2001 Kanji |
| 3a6.20 | The Kanji Dictionary |
| 1-3-6 | SKIP code |
| 3815.7 | Four corner code |
| 1-19-04 | JIS X 0208-1997 kuten code |
| 6d77 | Unicode hex code |
Jōyō kanji, taught in junior high
JLPT level N1
2031 of 2500 most used kanji in newspapers
Stroke order
On reading compounds
- 蛍光灯 【ケイコウトウ】 fluorescent lamp, fluorescent light, person who is slow to react, someone slow on the uptake
- 蛍光 【ケイコウ】 fluorescence
- 流蛍 【リュウケイ】 flying firefly
Kun reading compounds
- 蛍 【ほたる】 firefly (Luciola cruciata), lightning bug, glowworm
- 蛍藺 【ほたるい】 Scirpus hotarui (species of bulrush)
- 海蛍 【うみほたる】 sea firefly (Vargula hilgendorfii), seed shrimp
Readings
- Korean:
- hyeong
Spanish
- luciérnaga
Portuguese
- pirilampo
- vaga-lume
French
- ver luisant
- luciole
| 1200 | A Guide To Remembering Japanese Characters (Kenneth G. Henshall) |
| 1925 | A New Dictionary of Kanji Usage |
| 1717 | Japanese Kanji Flashcards (Max Hodges and Tomoko Okazaki) |
| 1878 | Kanji and Kana (Spahn and Hadamitzky) |
| 2043 | Kanji and Kana, 2nd Edition (Spahn and Hadamitzky) |
| 1676 | Kanji in Context (Nishiguchi and Kono) |
| 1607 | Kodansha Compact Kanji Guide |
| 3204 | Kodansha Kanji Dictionary (Jack Halpern) |
| 1658 | Kodansha Kanji Learner’s Dictionary (Jack Halpern) |
| 2248 | Kodansha Kanji Learner’s Dictionary, 2nd Edition (Jack Halpern) |
| 524 | Les Kanjis dans la tete (Yves Maniette) |
| 32983 | Morohashi |
| 2591 | New Japanese English Character Dictionary (Jack Halpern) |
| 5302 | New Nelson (John Haig) |
| 518 | Remembering The Kanji (James Heisig) |
| 557 | Remembering The Kanji, 6th edition (James Heisig) |
| 1482 | Tuttle Kanji Cards (Alexander Kask) |
| 3n8.2 | The Kanji Dictionary |
| 2-5-6 | SKIP code |
| 2-3-8 | SKIP code |
| 9013.6 | Four corner code |
| 3213.6 | Four corner code |
| 1-23-54 | JIS X 0208-1997 kuten code |
| 86cd | Unicode hex code |