Alternative form of fu: an administrative subdivision of imperial China; the capital of such divisions.
"The old barkeep knew that foo was just a silly way to spell fool when someone misheard it."
A metasyntactic variable used to represent an unspecified entity. If part of a series of such entities, it is often the first in the series, and followed immediately by bar.
Pronunciation spelling of fool.
In plain English: Foo is an informal term for someone considered silly or easily tricked.
"Don't be a foo and forget your keys again."
Usage: Use "foo" as a placeholder name for variables or values when writing code examples rather than using specific names like "x". Do not use this term to refer to an actual person or object outside of programming contexts.
Expression of disappointment or disgust.
"After seeing the ruined cake, he let out a loud foo to show how disappointed he was."
A mock deity of early science fiction fandom; a fannish ghod.
"In the bustling hall, the attendees bowed to the legendary foo as they passed through the main entrance."
The word foo comes from the Chinese character fú, which originally meant an official residence or government office. It entered English as a phonetic transliteration of this term before evolving into its current meaning in computing and science fiction contexts.