| 海 | hǎi | ocean; sea; CL:个,片 |
| 海军 | hǎi jūn | navy |
| 海上 | hǎi shàng | maritime |
| 海水 | hǎi shuǐ | seawater |
| 海外 | hǎi wài | overseas; abroad |
| 海底 | hǎi dǐ | seabed; seafloor; bottom of the ocean |
| 海关 | hǎi guān | customs (i.e. border crossing inspection); CL:个 |
| 海面 | hǎi miàn | sea level; sea surface |
| 海湾 | hǎi wān | bay; gulf (body of water); (Persian) Gulf |
| 海岸 | hǎi àn | coastal; seacoast |
| 海里 | hǎi lǐ | nautical mile; marine |
| 海峡 | hǎi xiá | channel; strait |
| 海南岛 | Hǎi nán dǎo | Hainan Island in South China Sea |
| 海域 | hǎi yù | sea area; territorial waters; maritime space |
| 海港 | hǎi gǎng | seaport; harbor |
| 海牙 | Hǎi yá | The Hague (city in the Netherlands); Den Haag |
| 海运 | hǎi yùn | shipping by sea |
| 海参 | hǎi shēn | sea cucumber |
| 海员 | hǎi yuán | sailor; mariner |
| 海盗 | hǎi dào | pirate |
| 海边 | hǎi biān | seaside |
| 海岛 | hǎi dǎo | island |
| 海滨 | hǎi bīn | shore; seaside |
| 海岸线 | hǎi àn xiàn | coastline; seaboard; shoreline |
| 海内 | hǎi nèi | the whole world; throughout the land; everything under the sun |
| 海绵 | hǎi mián | sponge |
| 海防 | hǎi fáng | coastal defense |
| 海口 | hǎi kǒu | estuary; coastal inlet; river mouth; seaport; see also 夸海口; Haikou prefecture-level city and capital of Hainan Province 海南省 |
| 海滩 | hǎi tān | beach; CL:片 |
| 海上花列传 | hǎi shàng huā liè zhuàn | The Sing-Song Girls of Shanghai by Han Bangqing 韩邦庆, long novel of lower life in classical Chinese and Jiangsu vernacular; translated into Putonghua as 海上花 by Iris Chang |
| 海平面 | hǎi píng miàn | sea level |
| 海南 | Hǎi nán | Hainan Province, in the South China Sea, short name 琼, capital Haikou 海口; Hainan Island; Hainan District of Wuhai City 乌海市, Inner Mongolia; Hainan Tibetan Autonomous Prefecture 海南藏族自治州, Qinghai |
| 海盐 | Hǎi yán | Haiyan county in Jiaxing 嘉兴, Zhejiang |
| 海带 | hǎi dài | kelp |
| 海藻 | hǎi zǎo | seaweed; marine alga; kelp |
| 海鸥 | hǎi ōu | seagull |
| 海地 | Hǎi dì | Haiti, the western third of Caribbean island Hispaniola |
| 海战 | hǎi zhàn | naval battle |
| 海风 | hǎi fēng | sea breeze; sea wind (i.e. from the sea) |
| 海王星 | Hǎi wáng xīng | Neptune (planet) |
| 海盗行为 | hǎi dào xíng wéi | piracy |
| 海船 | hǎi chuán | sea-going ship |
| 海马 | hǎi mǎ | sea horse |
| 海浪 | hǎi làng | sea wave |
| 海波 | hǎi bō | hypo (loanword); sodium thiosulfate Na2S2O3 used in fixing photos (formerly hyposulfite) |
| 海河 | Hǎi hé | Hai He (a system of five waterways around Tianjin, flowing into Bohai 渤海 at Dagukou 大沽口) |
| 海军陆战队 | hǎi jūn lù zhàn duì | marine corps; marines |
| 海涅 | Hǎi niè | Heinrich Heine (1797-1856), German lyric poet |
| 海产 | hǎi chǎn | marine; produced in sea |
| 海龟 | hǎi guī | turtle |
