- 复数域 fùshùyù field of complex numbersthe field of complex numbers in mathematics, usually denoted by the symbol C
- 共轭复数 gòng'èfùshù complex conjugatetwo complex numbers where the real parts are identical and the imaginary parts have opposite signs, such as "3+2i" and "3-2i"
- 复数平面 fùshùpíngmiàn complex plane(mathematics) complex plane; Argand plane
- 复数形式 fùshùxíngshì plural formThe plural form of a countable noun.
- 复数选举区 fùshùxuǎnqū multi-member constituencyan electoral district from which two or more representatives are chosen