Illustrating perfectly how wide this conversation really is, as we don't even have consensus about what "knowledge" means :)
Biology has a working definitions of "living organism" that includes a way to calculate likelihood that something is a living organism, but it still is probabilistic.
Understanding is another concept that depends on philosophy of the mind as opposed to concrete physical processes.
Wikipedia even has it's own page with some of the various definitions people use: https://en.wikipedia.org/wiki/Definitions_of_knowledge
Then we have implicit/explicit knowledge (https://en.wikipedia.org/wiki/Implicit_and_explicit_knowledg...) where some people assume one of them when they say "knowledge", others refer to the other.
In fact, there is an entire scientific field to understanding what "knowledge" actually is/means: https://en.wikipedia.org/wiki/Epistemology
So yeah, it isn't as simple as looking it up in a dictionary, unfortunately.