| 内 | nèi | inside; inner; internal; within; interior |
| 内容 | nèi róng | content; substance; details; CL:个,项 |
| 内部 | nèi bù | interior; inside (part, section); internal |
| 内外 | nèi wài | inside and outside; domestic and foreign; approximately; about |
| 内在 | nèi zài | intrinsic; innate |
| 内蒙古 | Nèi měng gǔ | Inner Mongolia; abbr. for Inner Mongolia autonomous region 内蒙古自治区 |
| 内战 | nèi zhàn | civil war |
| 内阁 | nèi gé | (government) cabinet |
| 内地 | nèi dì | inland; interior |
| 内政 | nèi zhèng | internal affairs (of a country) |
| 内心 | nèi xīn | heart; innermost being |
| 内能 | nèi néng | internal energy |
| 内燃机 | nèi rán jī | internal combustion engine |
| 内脏 | nèi zàng | internal organs; viscera |
| 内燃机车 | nèi rán jī chē | automobile |
| 内部矛盾 | nèi bù máo dùn | internal contradiction |
| 内存 | nèi cún | internal storage; computer memory; random access memory (RAM) |
| 内耗 | nèi hào | internal friction; internal dissipation of energy (in mechanics); fig. waste or discord within an organization |
| 内经 | Nèi jīng | same as 黄帝内经, Yellow Emperor's internal canon, medical text c. 300 BC |
| 内奸 | nèi jiān | undiscovered traitor; enemy within one's own ranks |
| 内行 | nèi háng | expert; adept; experienced; an expert; a professional |
| 内乱 | nèi luàn | internal disorder; civil strife; civil unrest |
| 内科 | nèi kē | medicine; "internal" medicine, i.e. treatment by administering drugs, as opposed to surgical intervention 外科; medical department |
| 内涵 | nèi hán | meaning; content; essential properties implied or reflected by a notion; intention; connotation; self-possessed |
| 内务部 | nèi wù bù | Ministry of Internal Affairs |
| 内罗毕 | Nèi luó bì | Nairobi, capital of Kenya |
| 内务 | nèi wù | internal affairs; domestic affairs; family affairs; (trad.) affairs within the palace |
| 内幕 | nèi mù | inside story; non-public information; behind the scenes; internal |
| 内皮 | nèi pí | (med.) endothelium; thin skin on the inside of some fruits (e.g. oranges) |
| 内人 | nèi rén | my wife (humble) |
| 内分泌 | nèi fēn mì | endocrine (internal secretion, e.g. hormone) |
| 内场 | nèi chǎng | infield (baseball) |
| 内情 | nèi qíng | inside story; inside information |
| 内衣 | nèi yī | undergarment; underwear; CL:件 |
| 内分泌腺 | nèi fēn mì xiàn | endocrine gland; gland producing internal secretion, e.g. hormone |
| 内涝 | nèi lào | waterlogged |
| 内丘 | Nèi qiū | Neiqiu county in Xingtai 邢台, Hebei |
| 内丘县 | Nèi qiū xiàn | Neiqiu county in Xingtai 邢台, Hebei |
| 内丹 | nèi dān | Taoist internal alchemy |
| 内兄 | nèi xiōng | wife's older brother |
| 内八字脚 | nèi bā zì jiǎo | intoeing; pigeon toes; knock-knees |
| 内出血 | nèi chū xuè | internal bleeding; internal hemorrhage |
| 内切球 | nèi qiē qiú | inside cut (golf) |
| 内化 | nèi huà | internalization; to internalize |
| 内卡河 | Nèi kǎ hé | Neckar river in Germany |
| 内参 | nèi cān | internal reference (within the same publication) |
| 内向 | nèi xiàng | inward-looking; introvert; introverted (personality); domestic-oriented (economy) |
| 内含体 | nèi hán tǐ | inclusion bodies |
| 内在几何 | nèi zài jǐ hé | intrinsic geometry |
| 内在几何学 | nèi zài jǐ hé xué | intrinsic geometry |
