FAZE
faze, unnerve, enervate, unsettle
(verb) disturb the composure of
Source: WordNet® 3.1
Etymology
Verb
faze (third-person singular simple present fazes, present participle fazing, simple past and past participle fazed)
(transitive, informal) To frighten or cause hesitation; to daunt, put off (usually used in the negative); to disconcert, to perturb. [from mid 19th c.]
Usage notes
The spelling phase is sometimes used for faze; including by such notables as Mark Twain and The New York Times.
Source: Wiktionary
Faze, v. t.
Definition: See Feeze.
Source: Webster’s Unabridged Dictionary 1913 Edition