Synonyms for Startling:

adj.

•amazing (adjective)
astounding.
•dramatic (adjective)
sensational.
•frightful (adjective)
shocking, surprising, alarming, unexpected, astonishing.
•surprising (adjective)
astounding, astonishing, shocking, surprising, sudden, unforeseen, unexpected, unanticipated.

n.

staggering, sensational, earth-shattering, remarkable, extraordinary, phenomenal. •shocking (noun)
frightful.
•startling (noun)
surprising.

v.

•alarming (verb)
frightening, Scaring, shocking, surprising, alarming, alerting, signaling, panicking, dismaying.
•surprising (verb)
catching unawares, taking aback, jolting, stunning.

Other synonyms:

•melodramatic
sensational.
•Other relevant words:
extraordinary, phenomenal, staggering, remarkable, sensational, astonishing, frightful.

Usage examples for startling

1. " Nothing startling dear lady. – The Shadow of the East by E. M. Hull

2. I ain't prepared to make any startling offer to a little girl that's just barely got her nose above the wall. – In the Bishop's Carriage by Miriam Michelson

3. You are the most startling person! – The Girl Scouts in Beechwood Forest by Margaret Vandercook