RichThesaurus
at one's wits' end
vs
fazed
at one's wits' end
fazed
adj
Hesitant, frightened; daunted, disconcerted; perturbed, put off (usually used in the negative).
How often have the words
at one's wits' end
and
fazed
occurred in a corpus of books?
(source:
Google Ngram Viewer
)