- quasi-differentiation
- quasi-diffusion
- quasi-diffusion method
- quasi-dihedral group
- quasi-directed set
- quasi-discrete
- quasi-discrete space
- quasi-discrete spectrum
- quasi-disjunction
- quasidisk
- quasi-dispersed set
- quasi-distance
- quasi distributed optical fiber measurement technique
- quasi-diurnal variation
- quasi-divisibility
- quasi-division ring
- quasi-divisor
- quasi-doubly-periodic function
- quasidual
- quasidual group
- quasidual space
- quasi-eigenfunction
- quasi-eigenvalue
- quasi-elastic light scattering
- quasi-elastic scattering