| 三亚市 | Sān yà shì | Sanya prefecture level city, Hainan |
| 三人口气 | sān rén kǒu qì | third person (grammar) |
| 三人成虎 | sān rén chéng hǔ | three men talking makes a tiger (idiom); repeated rumor becomes a fact |
三人行，
则必有我师 | sān rén xíng ,
zé bì yǒu wǒ shī | If three walk together, one of them can teach me sth (Confucius) |
三人行，
必有我师 | sān rén xíng ,
bì yǒu wǒ shī | lit. If three walk together, one should be my teacher (idiom, from Confucian analects). You have sth to learn from everyone.; also translated as: If three of us walk together, at least one of the other two is good enough to be my teacher. |
| 三仇 | sān chóu | animosity or resentment towards three groups (the bureaucrats, the wealthy, and the police) due to perceived abuse of power |
| 三代同堂 | sān dài tóng táng | three generations under one roof |
| 三件套式西装 | sān jiàn tào shì xī zhuāng | three-piece suit |
| 三伏 | sān fú | three periods forming the hottest periods of summer, from mid-July to mid-August, namely: 初伏 (mid-July), 中伏 (late July to early August), 末伏 (mid-August) |
| 三伏天 | sān fú tiān | three periods forming the hottest periods of summer, from mid-July to mid-August, namely: 初伏 (mid-July), 中伏 (late July to early August), 末伏 (mid-August) |
| 三位一体 | Sān wèi Yī tǐ | Holy Trinity; trinity |
| 三位博士 | sān wèi bó shì | the Magi; the Three Wise Kings from the East in the biblical nativity story |
| 三个代表 | sān gè dài biǎo | the Three Represents enunciated by Jiang Zemin 江泽民 as the duty of the Chinese Communist party in 2001, namely: to represent productivity of an advanced society, forward progress of advanced culture and the fundamental interests of the people |
| 三个女人一个墟 | sān gè nǚ rén yī gè xū | three women makes a crowd |
| 三个女人一台戏 | sān ge nǚ rén yī tái xì | three women are enough for a drama (idiom) |
三个臭皮匠，
合成一个诸葛亮 | sān gè chòu pí jiang ,
hé chéng yī gè Zhū gě Liàng | lit. three ignorant cobblers add up to a genius (idiom); fig. collective wisdom |
三个臭皮匠，
赛过一个诸葛亮 | sān gè chòu pí jiang ,
sài guò yī gè Zhū gě Liàng | lit. three ignorant cobblers add up to a genius (idiom); fig. collective wisdom; wisdom of the masses exceeds that of any individual |
三个臭皮匠，
赛过诸葛亮 | sān gè chòu pí jiang ,
sài guò Zhū gě Liàng | lit. three ignorant cobblers add up to a genius (idiom); fig. collective wisdom; wisdom of the masses exceeds that of any individual |
三个臭皮匠，
顶个诸葛亮 | sān gè chòu pí jiang ,
dǐng gè Zhū gě Liàng | lit. three ignorant cobblers add up to a genius (idiom); fig. collective wisdom; wisdom of the masses exceeds that of any individual |
| 三倍 | sān bèi | triple |
| 三价 | sān jià | trivalent |
| 三元区 | Sān yuán qū | Sanyuan district of Sanming city 三明市, Fujian |
| 三元运算 | sān yuán yùn suàn | ternary operator (computing) |
| 三元醇 | sān yuán chún | propyl alcohol C3H7OH |
| 三八 | sān bā | International Women's Day 妇女节[Fu4 nu:3 jie2], 8th March; foolish; stupid |
| 三八线 | sān bā xiàn | thirty eighth parallel, forming the DMZ border between North and South Korea |
| 三分之一 | sān fēn zhī yī | one third |
| 三分之二 | sān fēn zhī èr | two-thirds |
| 三分熟 | sān fēn shú | cooked three minutes; rare (of steak) |
| 三分钟热度 | sān fēn zhōng rè dù | brief period of enthusiasm; flash in the pan |
| 三十 | sān shí | thirty; 30 |
| 三十二位元 | sān shí èr wèi yuán | 32-bit (computing) |
| 三十八度线 | sān shí bā dù xiàn | thirty eighth parallel; dividing line agreed at Yalta between US and Soviet zones of influence in Korea, now the DMZ between North and South Korea |
| 三十六字母 | sān shí liù zì mǔ | thirty six initial consonants of Song phonetic theory |
| 三十六计 | sān shí liù jì | The Thirty-Six Stratagems, a Chinese essay used to illustrate a series of stratagems used in politics, war, and in civil interaction; all the possible schemes and stratagems |
三十六计，
走为上策 | sān shí liù jì ,
zǒu wéi shàng cè | Of the Thirty-Six Stratagems, fleeing is best.; see also 三十六计 |
| 三十天 | sān shí tiān | thirty days |
| 三十年来 | sān shí nián lái | for the past thirty years |
| 三十而立 | sān shí ér lì | thirty years old and therefore independent (idiom, from Confucius) |
| 三原则 | sān yuán zé | the Three Principles (in many contexts) |
| 三原县 | Sān yuán xiàn | Sanyuan county in Xiányáng 咸阳, Shǎnxī 陕西 |
| 三叉神经 | sān chā shén jīng | trigeminal nerve |
| 三反 | sān fǎn | "Three Anti" campaign (anti-corruption, anti-waste, anti-bureaucracy), early PRC purge of 1951-52 |
| 三反运动 | sān fǎn yùn dòng | "Three Anti" campaign (anti-corruption, anti-waste, anti-bureaucracy), early PRC purge of 1951-52 |
| 三台县 | Sān tái xiàn | Santai county in Mianyang 绵阳, north Sichuan |
| 三合一 | sān hé yī | three in one; triple |
| 三合一疫苗 | sān hé yī yì miáo | DTP vaccination |
| 三合土 | sān hé tǔ | mortar; concrete; cement |
| 三合星 | sān hé xīng | triple star system |
| 三合会 | Sān hé huì | Triads, organized crime society; Triad Society (early Qing anti-Manchu secret society) |
