un ‧ nerve /ʌnˈnɜːv $ -ɜːrv/ BrE AmE verb [transitive]
[ Word Family: adjective : ↑ nervous , ↑ nerveless , ↑ nerve-racking , ↑ nervy , ↑ unnerving ; noun : ↑ nerve , nerves, ↑ nervousness ; verb : ↑ nerve , ↑ unnerve ; adverb : ↑ nervously ]
to upset or frighten someone so that they lose their confidence or their ability to think clearly:
He was unnerved by the way Sylvia kept staring at him.
—unnerving adjective :
an unnerving experience