I would define intellectual dishonesty, in its most basic form, as lying to oneself. If you're intentionally lying to others, you're being dishonest with them.

I would define intellectual dishonesty, in its most basic form, as lying to oneself. If you're intentionally lying to others, you're being dishonest with them. But if you're glossing over your own second-guesses, or taking shortcuts you know to be lazy, or not bringing as much rigor to a situation as you know you are capable of bringing, then you are in some ways "lying" to yourself. Either you are not using your full intellectual capabilities, or you are convincing yourself that you have when you have not. In this sense, "lack of scientific rigor" would be a subset of intellectual dishonesty. It's not always undertaken in bad faith, but when it's undertaken consciously, then it's dishonest.