"Insubordination" means "defiant conduct" or "rebellious behavior" in the context of employee/employer interaction. Examples include, but are not limited to, mouthing off; wisecracks; a stubborn or disgruntled look on a worker's face when told to do something; lying; disobedience, and refusal to follow "the rules." Of course, yelling at the boss in a hostile tone would probably fit the bill. Cursing at a superior may fall under two or three headings on the list of what gets you canned. Insubordination could easily be one. Writing an email about your boss, that big jerk, could be seen as insubordinate; in fact, I know someone who did exactly that. The big jerk saw the email, and she found out what "insubordinate conduct" and "failure to follow written company policy on electronic mail." meant, in practical terms. Management was looking for a viable reason to let her go and they got it. Caught red-handed...and red-faced, too. Picture a small child, standing, with arms crossed, lips pressed tightly together, shaking his head at whatever his parents are saying. Now carry that image over into adulthood, with the former brat as a grown man, and one of his parents as his boss. That's how I see insubordination. As the HR Manager for a restaurant chain here in Southern California for six years, I saw it on almost every level. Except, of course, those of us toiling diligently and gracefully away behind the scenes at the Elephant Bar corp. office. Insubordination was pointless with my supervisor, anyway. She was a great person and a wonderful boss. Brilliant. And when the occasional dicey situation arose, you couldn't find a better ally. She was just about the funniest person I've ever known. It's a miracle that anyone got anything done when we were both in the office. Her father was a hot-shot defense attorney in LA and she had the routine down cold. When insubordination met Michele Bennett, Michele talked and attitude wilted. Then it was all over but the laughter. I'm digressing, but, it's a nice memory that's forgotten too easily, so just bear with me. Thanks. Back to reality - rolling your eyes behind your employer's back and smirking could be called insubordinate if he or she somehow knew what was happening and didn't like it. ( IF? How silly. We all enjoy that.) Or, maybe something milder, like saying, "No thanks" to overtime, although that's reaching. But, if the boss needs an excuse....well, you get the idea. To sum it up, insubordination is an action, behavior, mannerism, and/or attitude, as well as display or pattern of conduct that could reasonably be interpreted as disrespectful to the authority of a supervisor. It doesn't matter if the rebellious employee is right or wrong. At least not until he or she seeks monetary compensation for wrongful termination, but believe me, that's a category all its own. Good luck - it's a jungle out there!