Congress has no authority to re-define constitutional terms. Neither do the Courts. The Constitution is the SOURCE of their power, they are not the masters.
The Only Authority capable of re-defining constitutional terms is the combined effect of both House and Senate with 3/4ths of the State Legislatures voting in the affirmative.
DiogenesLamp wrote: “Congress has no authority to re-define constitutional terms.”
So they asked the experts they employ.