SB,

Don't worry about the shriveled flower stem on this particular phal hybrid.

Yes, some phals will rebloom from a flower stem. For instance, there are a ton of sequential bloomers, the kind with (usually) starry shaped flowers that are produced 1-3 at a time. Those will bloom for years off the same spike. Then you have the more traditional multifloral phals (like you've got) that will sometimes, but definitely not always, flower from the same stem if cut back to the right point. What happens is, the stem produces a new branch, and will bloom off that.

Purely anecdotal, but I've also never seen one of the smaller multifloral varieties of phal (doritaenopsis) rebloom off an old stem, so you might never experience that with your particular plant.

I can't answer your last question because I don't know what it means, other than to say yes, the common name for a phalaenopsis is the moth orchid.