Qualified retirement plan
A qualified retirement plan is a plan that meets the requirements of Internal Revenue Code Section 401(a)  and the Employee Retirement Income Security Act of 1974 (ERISA) and therefore qualifies for favorable tax treatment.
For the employer, these plans allow deduction of annual allowable contributions by each participant.
For the employee, contributions and earnings are tax-deferred until withdrawn.
- 26 USC § 401 - Qualified pension, profit-sharing, and stock bonus plans, Legal Information Institute , Cornell University Law School]
Definitions of qualified retirement plan on Google
Qualfied Retirement Plan, on Investorglossary.com