Hey, kids! Let's stop using the term "intrinsically evil"!
I know, it's widely used and accepted in moral theology. But it's also widely mis-used, and misunderstood even when it's used correctly.
I've seen "intrinsically evil" used to mean four distinct things:
"Objectively evil," which describes an act that is evil in its object, where the object specifies the act that is being performed. This, I gather, is the proper sense of the term; at least, it's how it's used in e.g. Veritatis Splendor.
"Gravely evil," which describes an act of, uh, grave evil. It is a common error to think that objective evil implies grave evil, and the time spent discussing the error is time not spent recognizing that in either case you're talking about something evil.
"Categorically evil," which describes an act that is evil no matter what. The "what" can only be circumstances and intentions that aren't already specified in the act. They can't be another object, since different objects specify different acts; they can't be circumstances or intentions that replace or supplant the circumstances and intentions that contribute to specifying the category of the act.
"Evil," which describes an act that lacks goodness. People sometimes call an act "intrinsically evil" when all they really mean, need, or can justify is "evil."
Better to use four distinct and distinguishable terms than to use one term whose meaning in a particular case isn't always easily distinguished.