Defined benefit plan and defined contribution plan
For purposes of this title, the term “defined contribution plan” or “defined benefit plan” means a defined contribution plan (within the meaning of section 414(i)) or a defined benefit plan (within the meaning of section 414(j)), whichever applies, which is—
(A)#
a plan described in section 401(a) which includes a trust which is exempt from tax under section 501(a),
(B)#
an annuity plan described in section 403(a),
(C)#
an annuity contract described in section 403(b), or
(D)#
a simplified employee pension.