A word that has been assigned a classification and a
classified meaning to safeguard intentions and
information regarding a classified plan or operation.
That is to say, the meaning of a code word is generally classified. It's not just a convenient label; its purpose is to obfuscate even the general intent behind . . . whatever's going on under that umbrella.
If they think it's been compromised--that is, if they think someone has figured out UMBRA=COMINT--they'll generally change it. If it's made it all the way onto Wikipedia, they probably changed it long ago. And if it isn't redacted in declassified materials, they definitely changed it long ago.
Though it's always possible that they just don't care anymore. Sometimes programs persist under their code words long after what they're doing isn't classified anymore.
