As a noun, interchangeable with (and cleaner than) "bullshit," "no f---ing way," et cetera. As an adjective, describes something exhibiting the aforementioned qualities to a ridiculous degree, often to the point of being borderline fantasy. Comes from a particular individual's inability to state true facts without the aid of a book.
As a noun:
"We understand the concept of Hitler being cryogenically frozen at the end of World War II, in order to preserve his brain for future research."
"I call delto."
As an adjective:
"What? Al Gore was president? Man, that is delto."
"We understand the concept of Hitler being cryogenically frozen at the end of World War II, in order to preserve his brain for future research."
"I call delto."
As an adjective:
"What? Al Gore was president? Man, that is delto."
by Horse Brigadier February 24, 2008