；完满拉丁方；完满正方形- twistor space
- twistor theory
- twist-spun knot
- twist theorem
- twi- (= twy-) 【前缀】
- two arrows space
- two-body interaction
- two-body problem
- two-cardinal
- two-colorable graph
- two-column proof
- two-combination
- two-component function
- two-component spinor
- two-connected
- two-constant theorem
- two-decision problem
- two-digit integer
- two-dimensional
- two-dimensional annulus
- two-dimensional cell
- two-dimensional chain
- two-dimensional cocycle
- two-dimensional complex
- two-dimensional covering