It’s not in the Constitution - correct. There is also nothing in the Constitution which grants license to judges or anyone else to disregard the concept of language, yet these judges have done so.
Changing the definition of a word and a legal term is troubling, in my opinion.
Last year’s Supreme Court decision on marriage indicated that the federal government had to recognize same sex marriages from states which allowed it. BUT THIS ACTION ALSO set up a situation in which the federal government is not allowed to define a legal definition of the legal term marriage.
Now it appears that only federal judges are allowed to define the legal term marriage.