401-k(n = noun.cognition) 401-k plan - a retirement savings plan that is funded by employee contributions and (often) matching contributions from the employer; contributions are made from your salary before taxes and the funds grow tax-free until they are withdrawn, at which point they can be converted into an IRA; funds can be transferred if you change employers and you can (to some extent) manage the investments yourself;
is a kind of pension account, pension plan, retirement account, retirement plan, retirement program, retirement savings account, retirement savings plan