Dubiety

Dubiety is a sense of misgiving; conceivably, even if you have no real doubt in the correctness of a course of action, you can still feel dubiety at having to be the one who follows it.

This is a good word to use for those who struggle with decisions. "Quit focussing on every dubiety and act on what you think is best." "Doctors often have no time for even the slightest dubiety before removing defective parts of your anatomy."

My take on words
I like your dictionary because it described the word dubiety to a tittle. Note my intention here was just to use the new phrase "something to a tittle" which is same as "something to a t" i.e completely. The martinet professor commanded the young lad to forget his dubiety and focus on cramming the new words for now and worry later about their exact usage.