Learn English – “Open source” as a verb

Want is not causative.

A Causative verb can be paraphrased as "cause S to be true", where S is some proposition that might refer to

• an event (e.g, cause it to explode)
  They exploded the bomb they'd dug up
• an action (cause someone to trip)
  His older brother tripped him accidentally
• a state (cause someone to be dead)
  We wouldn't have to kill anyone

These are, respectively, paraphrases for the causative transitive verbs explode, trip, and kill. All causative verbs are transitive, and there often exist intransitive inchoative verbs with the same shape (it exploded, he tripped); but not always (he died, but not *he killed -- at least not in the same sense as he died).

Wanting, of course, causes nothing to happen by itself, though it can serve as a motivation. As Barrie says, it's a mental state verb, very close to the deontic sense of the modal verb will (in German the modal verb wollen straightforwardly means 'to want').

Usually you can just slap re on the front of a word, without a hyphen, and you will be understood. There’s no need for the term to have made its way into an “authoritative” dictionary, even if there were such a thing.

There are circumstances in which the hyphen is desirable:

• if your new word with re collides with an established “re” word which has a different sense. Two of the words Carlo_R mentions are of this sort: resign and reserve.
• If you want to draw attention to the fact that you are using a “re” word in a different sense than that which would be expected, particularly if you are reverting to the base sense. “D.W.Griffith’s re-construction of the myth of the carpetbagger.”
• If you want to emphasize that you are repeating or reversing an action. “Burns opened an interesting question in 1923; but it has been completely neglected and I want to re-open it now.”

I sometimes intrude a hyphen when the word to which I’m attaching re begins with a vowel, to prevent even momentary confusion; but it’s probably not necessary.