Plumbing - parts and lingo question

My experiences as a do-it-yourselfer when it comes to plumbing have taught me to actually take the pieces in question to the bricks-and-mortar store with me and fit them to the parts I'm buying. There are a dizzying number of different types of fittings, and many of them LOOK like they should fit together. It's only by trying the fit - hand-on - that you're able to be sure you have the right thing. I would not advise you to continue to try to get the lingo right just in order to get the job done. It will be quicker and easier to take the parts in to the store with you - whatever they are called. Of course, if you just want to know the names of the parts in order to be well-educated, that's another story. I would never try to get plumbing fixtures online.

-Speak