How do you define a cockold?

Recently a question came up in my life for reasons that are probably best explained with ADHD.

While it might appears to be google-able question the answer are all very different, I would like to hear your opinions.

Anyway the question that lead me to the question above is the following "assuming you would have a reasonable expectation to have sex with a person, e.g. you paid a prostitute, and that person would end up having sex with another person instead and you wouldn't get to do it too, would you be cockold?"

Thanks.