Synonyms for Frightened:

adj.

all (adjective)
scared.
amazed (adjective)
shocked.
cowardly (adjective)
weak-kneed.
fearful (adjective)
afraid, cowardly.
frightened (adjective)
scared, terror-stricken, paralyzed, fearful, afraid, petrified, anxious, rattled, lily-livered, agitated, unnerved, weak-kneed, intimidated, terrified, apprehensive, Harrowed, alarmed, jittery, timid, scared stiff, chicken-livered, startled, cowardly, fainthearted, horrified.
very scared (adjective)
panicky, fearful, scared stiff, anxious, dismayed, terror-stricken, afraid, jittery, unnerved, lily-livered, petrified, alarmed, terrified, startled.

n.

(with) your heart in your mouth. on edge, troubled, nervous, tense, upset, uneasy, worried. frightened (noun)
terrified, panic-struck, afraid, panic-stricken, panicky, panicked, scared.
scared (noun)
study at afraid.

v.

alarmed (verb)
surprised, shocked, Signaled, alerted, dismayed.
frightened (verb)
set on edge, haunted, disturbed, panicked.
threatened (verb)
browbeaten, Foreboded, bullied, Forewarned, scared, tormented, threatened, admonished, harassed, intimidated, Bulldozed, Hinted, browbeat.

Other synonyms:

tense, uneasy. nervous, worried. worried
troubled.
Other relevant words:
nervous, uneasy, on edge, troubled, worried, tense, panic-struck, upset, panic-stricken, panicky.

Usage examples for frightened

  1. As usual he looked frightened and hurried away. – Cord and Creese by James de Mille
  2. " The only time I get frightened in life is when things look like that," Ingolby answered. – The World For Sale, Volume 2. by Gilbert Parker
  3. She looked at him, frightened – The Mystery of The Barranca by Herman Whitaker