Sentence:  [I]f you knew how Selina feels with respect to sleeping at an inn, you would not wonder at Mrs. Churchill's making incredible exertions to avoid it. Selina says it is quite horror to her—and I believe I have caught a little of her <WSD>nicety</WSD>. 
Meaning of the word marked with <WSD> tags:  Delicacy of character or feeling usually from excessive refinement; fastidiousness