Is 'Reason' Ambiguous?

There hasn't been much activity recently, so I doubt that anyone looks at this blog very frequently anymore. But I suppose that posting any current thoughts here is more likely to provoke responses than if I did not post them at all. So, here goes.

I'm taking a course in meta-ethics this semester, and one issue that we have recently been considering has to do with whether or not moral propositions are reasons for acting in a certain way. For instance, it is arguably the case that that it is wrong for Smith to kick Jones is a reason for Smith to refrain from kicking Jones and that giving money to charity is right is a reason to give money to charity.

All of this has got me thinking about 'reason'-talk in general. It seems clear to me that 'reason' is not a philosophical term of art, but rather that it is an ordinary term of English. (If anyone has any doubts about that, I suggest they do a Google search for 'is a reason to' or 'there are many reasons to' and see what they turn up.) So information concerning its use by ordinary English speakers as well as information concerning when such use embeds it in true English sentences is of significant importance to answering philosophical questions concerning its meaning and concerning the sorts of things it applies to.

One important question concerning 'reason' is whether or not it is ambiguous. (In saying this I don't mean to rule out that theories according to which cases of apparently ambiguous words like 'bank' are to be explained rather by appeal to the existence of two different words whose spelling is the same. In fact, I am sympathetic to such theories. However, it is easier to speak as if there was one word here that has different meaning when used in different ways, and so I do that here.) It seems pretty clear to me that 'reason' is ambiguous. Too see this consider it as used in the following sentence:
(1) There's at least one reason to go to the bank.
and contrast the meaning it has in that sentence with the meaning it has in the following:
(2) Reason is the primary faculty of man.
It is rather clear to me that, although it is used as a noun in both (1) and (2), its meaning in (1) is significantly different from its meaning in (2). (For one thing it is used as a singular term in (2), but not in (1)!)

A more significant question is whether 'reason' is ambiguous between a sense on which it applies solely to "practical reasons", a sense on which it applies solely to "moral reasons", and a sense on which it applies solely to "epistemic reasons". My guess is that it is not. Consider the following sentences:
(3) One reason to refrain from shooting Smith is that shooting Smith is wrong to do.
and
(4) One reason to believe that there is something that is wrong to do is that shooting Smith is wrong to do.
It seems pretty clear to me that from (3) and (4) we can validly infer:
(5) That shooting Smith is wrong to do is a reason to refrain from shooting Smith and to believe that there is something that is wrong to do.
(By saying that the inference is valid, I do not mean that it is syntactically valid, but rather simply that it is necessarily truth-preserving.) But that this inference is valid suggests that 'reason' is not used in different senses in (3) and (4), and thus that it is not ambiguous between "epistemic" and "practical" senses. A similar argument can be made to show that there is no ambiguity in the use of 'reason' between "moral" and "practical"/"epistemic" senses.