Does it show the Measure tool? If so, did you click and hold over that tool?
Mystery solved... the fix was actually quite easy. I don't know where the eyedropper went, but I did a "Find File" search on my iMac and could see that there was still an Eyedropper plug-in within my files. So I did some more research online and someone with a similar problem on Adobe Communities had been advised to replace their InDesign preferences because they must have been corrupted. I'm trying to post the URL where the info was, but since I had to sign in to Adobe to access the information, I can't post a direct link. Once you're in Adobe Communities, it was under the thread titled "Troubleshooting 101: Replace, or "trash" your InDesign preferences
Actually, what Peter Spier, the respondent, said in a nutshell was this:
[When InDesign starts to behave strangely, the number one suggestion for troubleshooting is to replace (or trash, reset or restore) the application preferences. This will remove corrupt preferences and replace them with a new set of default preferences, and often end bad behavior.
There is a quick and easy method for doing this using the keyboard: close and relaunch InDesign, and IMMEDIATELY hold down Ctrl + Alt + Shift (Windows) or Cmd + Ctrl + Opt + Shift (Mac), and respond in the affirmative to the dialog asking if you really want to replace the preferences. There are two downsides to this method, however. First, you must be extremely fast on the keyboard (if you don’t see the confirmation prompt, you were too slow), and second, anytime you replace the preferences you will lose most program customizations, and using the keyboard method leaves you with no backup to restore them when the problem turns out to be something else.
My preferred method is to CLOSE INDESIGN and do a “manual” prefs replacement, which consists of finding and renaming the two files which make up the preference set: InDesign Defaults and InDesign SavedData. BOTH of these files should be replaced at the same time. You can delete them, but renaming or moving them will give you the opportunity to copy them back in the event that new prefs doesn’t cure your issue. When you restart ID, the program will look for these two files, and when they are not found, a new default set will be written.]
I did the first method... Cmd + Ctrl + Opt + Shift on my Mac. Eyedropper magically reappeared in the toolbar on the left. Easy peasy.
Appreciate your attempt to help. The online community can be pretty awesome sometimes.
Thank you!!! I was having the same problem! I thought I was going crazy!