1.) To be in league with a crime, or conspiracy. Also to mean in alliance with or secret partnership with.
2.)To be a lover, or someone you like very much. Commonly used by someone how is annoyed or displeases with someone else.
(Note: this is slang, coming from the word/slang "ca" meaning: used to express a certain feeling of fondness for a person. Also the words "hoots" meaning: the characteristic cry of an owl)
"Don't trust anyone on that road there are often robbers that are in cahoots with each other!"
"Where are they? Idk? I bet there off in cahoots some where..."
I met this girl last night, and we did the Cahoot!
originated from owls which are very cleverly disguised like trees so people wandering through a forest cannot tell where the ominous hooting is from, even though the owl is obviously on the branch right in front of them...