bool

A Boolean variable (one whose value is either true or false).

Noun

A Boolean variable (one whose value is either true or false).
- The base class BitArray acts just like a normal C++ array of bools, although you are of course free to interpret the bits as integers […] - 2000, Mark A DeLoura, Game programming gems:
- With an automatic conversion, bools will interfere with overload resolution […] - 2000, Herb Sutter, Exceptional C++:
- Listing 7-11 shows an example where the initial data type is string, but I will obtain its value as a bool. - 2007, Joseph C Rattz, Pro LINQ: Language Integrated Query in C# 2008:

From a keyword in C++ and derived programming languages, short for Boolean.

To relax or hang out (especially with someone).
- I'm going to go bool with the boys.
- You want a war, steady coming for the team / I'm just booling with my dogs, don't make me let 'em off the leash - 2017 November 27, “I'm A Dog”, in Dotarachi HD Reloaded, performed by S Dot:
- YG's starting the year strong with a new video for his 2018 single "Suu Whoop," released on Tuesday. In the gritty visual, we see the L.A. native booling with his friends in his city’s streets, in cars, outfitted in red...

Likely from replacement of the 'c' in cool.