| 光临 | guāng lín | (honorific) Welcome!; You honor us with your presence.; It is an honor to have you. |
| 光州 | Guāng zhōu | Guangzhou, old name for Huangchuan 潢川 in Xinyang 信阳, Henan; Gwangju Metropolitan City, capital of South Jeolla Province 全罗南道, South Korea |
| 光二极管 | guāng èr jí guǎn | photodiode; light-emitting diode (LED) |
| 光亮度 | guāng liàng dù | brightness; luminosity |
| 光伏 | guāng fú | photovoltaic (e.g. cell) |
| 光伏器件 | guāng fú qì jiàn | photovoltaic device (e.g. solar cell) |
| 光信号 | guāng xìn hào | optical signal |
| 光光 | guāng guāng | bright; shiny; smooth; naked; bald; penniless |
| 光刻 | guāng kè | photolithography |
| 光刻胶 | guāng kè jiāo | photoresist (laser etching used in microelectronics) |
| 光前裕后 | guāng qián yù hòu | to bring honor to one's ancestors and benefit future generations (idiom) |
| 光功率 | guāng gōng lǜ | optical power |
| 光动嘴 | guāng dòng zuǐ | empty talk; mere rhetoric; palaver |
| 光化作用 | guāng huà zuò yòng | photochemical effect; photosynthesis; photolysis |
| 光化学 | guāng huà xué | photochemistry |
| 光合 | guāng hé | photosynthesis |
| 光学仪器 | guāng xué yí qì | optical instrument |
| 光学字符识别 | guāng xué zì fú shí bié | optical character recognition, OCR |
| 光学显微镜 | guāng xué xiǎn wēi jìng | optical microscope |
| 光宗耀祖 | guāng zōng yào zǔ | to bring honor to one's ancestors |
| 光射线 | guāng shè xiàn | light ray |
| 光导纤维 | guāng dǎo xiān wéi | optical fiber |
| 光山县 | Guāng shān xiàn | Guangshan county in Xinyang 信阳, Henan |
| 光州市 | Guāng zhōu shì | Guangzhou, old name for Huangchuan 潢川 in Xinyang 信阳, Henan; Gwangju Metropolitan City, capital of South Jeolla Province 全罗南道, South Korea |
| 光州广域市 | Guāng zhōu guǎng yù shì | Gwangju Metropolitan City, capital of South Jeolla Province 全罗南道, South Korea |
| 光年 | guāng nián | light-year |
| 光彩夺目 | guāng cǎi duó mù | dazzling; brilliant |
| 光影 | guāng yǐng | light and shadow; sunlight and shade |
| 光影效 | guāng yǐng xiào | lighting effect |
| 光复乡 | Guāng fù xiāng | Guangfu or Kuangfu township in Hualien county 花莲县, east Taiwan |
| 光怪陆离 | guāng guài lù lí | monstrous and multicolored; grotesque and variegated |
| 光感应 | guāng gǎn yìng | optical response; reaction to light; light sensitive; photoinduction |
| 光接收器 | guāng jiē shōu qì | optical receiver |
| 光斑 | guāng bān | facula |
| 光明新区 | Guāng míng xīn qū | New Guangming district of Shenzhen City 深圳市, Guangdong |
| 光明星 | guāng míng xīng | bright star; name of North Korean space satellite |
| 光明节 | Guāng míng jié | Hanukkah (Chanukah), 8 day Jewish holiday starting on the 25th day of Kislev (can occur from late Nov up to late Dec on Gregorian calendar); also called 哈努卡节 and simply 哈努卡 |
| 光柱 | guāng zhù | light beam; light pillar (atmospheric optics) |
| 光棍儿 | guāng gùnr | single person; bachelor |
| 光棍节 | Guāng gùn Jié | Singles' Day |
| 光槃 | guāng pán | variant of 光盘, compact disc; CD or DVD; CD ROM |
| 光标 | guāng biāo | cursor (computing) |
| 光检测器 | guāng jiǎn cè qì | optical detector |
| 光波长 | guāng bō cháng | optical wavelength |
| 光溜 | guāng liū | smooth; slippery |
| 光漆 | guāng qī | enamel |
| 光泽县 | Guāng zé xiàn | Guangze county in Nanping 南平 Fujian |
| 光爆 | guāng bào | explosion of light |
| 光环 | guāng huán | halo; ring of light |
| 光发送器 | guāng fā sòng qì | optical transmitter |
