1
- one of two children or animals born at the same birth孪生子之一; 双胞胎之一。
1.1
- a person or thing that is exactly like another两个非常相像的人（或物）中的一个：
there was a bruise on his cheek, a twin to the one on mine.
他的面颊上有块淤伤, 和我的一模一样。
1.2
the Twins
the zodiacal sign or constellation Gemini双子星座。
2
- something containing or consisting of two matching or corresponding parts, in particular成对, 成双的东西, 尤指：
2.1
- a twin-bedded room（有一对单人床的）双人间。
2.2
- a twin-engined aircraft双引擎飞机。
2.3
- a twinned crystal孪晶体。
attrib.
1- forming, or being one of, a pair born at one birth孪生的：
she gave birth to twin boys
她生了对双胞胎儿子
her twin sister.
她的孪生姐妹。
1.1
- forming a matching, complementary, or closely connected pair孪生的, 成对的, 成双的：
the twin problems of economic failure and social disintegration.
经济失败和社会解体这对孪生问题。
1.2
- Botany growing in pairs【植】双生的：
twin seed leaves.
双生子叶。
1.3
- (of a bedroom) containing two single beds（卧室）有两张单人床的。
1.4
- (of a crystal) twinned（晶体）孪晶的。
1
twinned, twinning
with obj.（一般作be twinned）Brit. link (a town or district) with another in a different country or cause (two towns or districts) to be linked, for the purposes of friendship and cultural exchange〈英〉（为友谊、文化交流目的而）结成姐妹城：the Russian city of Kostroma is twinned with Durham.
俄国的科斯特罗马市与达勒姆结为姐妹城。
1.1
- link; combine连接; 联合：
the company twinned its core business of brewing with that of distilling.
这家公司将其核心业务酿造和蒸馏联合起来。
词源
late Old English twinn 'double', from twi- 'two'; related to Old Norse tvinnr. Current verb senses date from late Middle English.