In addition to your employer contribution, you contribute a set amount of money to your retirement ...

D - defined contribution plan

Defined-contribution retirement plans include money-purchase plans and profit-sharing plans. In a money-purchase plan, the employer promises to contribute a set percentage of salary. For example, your employer might promise to add 3 percent of your salary to a retirement account each year. In a profit-sharing plan, the employer's contributions are discretionary but are often a percentage of either profits or salary. As with a money-purchase plan, the employer might pay 3 percent per year into your account, but if profits are down, management can choose not make a contribution at all.