A lie is saying something that's not true. It's not suppressing the a compulsion to act like a total jackass, no matter how much you really want to. If my boss asked me for an opinion on something I thought was a bad idea, I'd express my thoughts (with empathy). Honesty is not immediately blurting out every thought that passes through your mind, and it's not dishonest to withhold information that people aren't entitled to. You're (perhaps intentionally) confusing honesty with openness. Sometimes it takes courage to be honest, but in my opinion, there's more dangers in dishonesty.

I've never thought my boss was a "fucking moron". While there have been things that have made me frustrated or irritated, I believe I have enough maturity, and so does he, that we can talk like adults and either come to a compromise or better understand their actions/decisions and them understand mine.

I don't know what kind of world you live in where not blurting out the first insulting comment is considering lying...

Holding your tongue does not make you a liar.

Not sharing every thought you have does not make you a liar.

Everyone is not required (Thank God!) to reveal everything that crosses their mind in order to be truthful and honest.

You have a very warped definition of "dishonesty".