What gobbeldygook means
Gobbledygook is a word or phrase that is so convoluted and complicated, it can’t be deciphered. Some examples of gobbledygook are legalese, military acronyms, and big words that you don’t know the meaning of. They may seem silly to speak or write in the first place, but they’re often used in order to make something sound more intelligent or important than it actually is. They may also be used to thwart people from easily understanding what the gobbledygook actually means, or they may even be helpful to confuse people on purpose.
Here are some examples of gobbledygook you might already be familiar with:
TANSTAAFL – There Ain’t No Such Thing As A Free Lunch.
WETA – Weapon Enhancement Technology And The Art Of War.
UPSIDE – Upstream Processing and Storage Facility. [Identified as this in the olden days] (UPSIDE stands for Above Topsecret, which was a US military document that was declassified in 2001. The document was the result of analysis done by analysts and scientists at the Army’s Electronics and Telecommunications Command, or ELTECOM as it is now known, on a series of UFO sightings.)
ET – Electronic Technical.
SDB – Space Development Board (or in shorter form, SDB!)
DoD – Department Of Defense. This can be seen in a lot of government documents, such as military manuals. The DoD stands for the Department Of Defense.
The following is an excerpt from a dictionary:
gobb·ledygook \GOB-bəl-dij-gook\ noun: gobbledygooknoun: gobbledygooka piece of wording that is so convoluted and complicated, it can’t be deciphered.

Where the word comes from
The word “gobbledygook” is derived from the phrase “gobbledygook and doubletalk,” which comes from a story about a man who was trying to teach his son about life. The man told his son, “Son, there are two birds in the world that you need to watch out for. One is called a ‘gobble-gobble’ and the other is called a ‘doubletalk.’ A doubletalk looks like a turkey on the outside, but inside he’s nothing but gobbledygook.”
This story is about a man who wants his son to understand that there are two things in the world that you need to watch out for: “One is called ‘gobbledygook’ and the other is called ‘doubletalk.’ A doubletalk looks like a turkey on the outside, but inside he’s nothing but gobbledygook.”
The man tells his son: “If you want to become a great hunter, then look out for the gobbledygook. If you want to stay alive, look out for the doubletalk.”
This story is similar to:
You woo a lady and then you go to court. If a man is paid to woo a lady, that’s called ‘wooing.’ Then he goes to court. If he wins the case, that’s called ‘winning.’ But if he loses the case, it’s still called wooing. And if a lady is paid to get into court and win the case, then that’s called ‘doubletalk.’
And here is an example from the movie The Illusionist (2005) where a character says: “If you want to be a magician, then watch out for gobbledygook.”