Dictionary.com
Thesaurus.com
Synonyms

startle

American  
[stahr-tl] / ˈstɑr tl /

verb (used with object)

startled, startling
  1. to disturb or agitate suddenly as by surprise or alarm.

    Synonyms:
    astonish, frighten, scare
  2. to cause to start involuntarily, by or as by a sudden shock.


verb (used without object)

startled, startling
  1. to start involuntarily, as from a shock of surprise or alarm.

noun

  1. a sudden shock of surprise, alarm, or the like.

  2. something that startles.

startle British  
/ ˈstɑːtəl /

verb

  1. to be or cause to be surprised or frightened, esp so as to start involuntarily

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Related Words

See shock 1.

Other Word Forms

  • outstartle verb (used with object)
  • startlement noun
  • startler noun

Etymology

Origin of startle

First recorded before 1100; Middle English stertlen “to rush, caper,” equivalent to stert(en) “to begin, start” ( start + -(e)len -le, or continuing Old English steartlian “to kick, struggle”

Explanation

To startle is to jump, like when you're surprised. If you’re sneaking through a dark room and step on a sleeping dog’s tail — you might startle the dog. If she barks, that dog startles you right back! A startle is a quick, sharp movement, like a little jump that happens when you’re surprised or suddenly scared. If you sneak up on your mom and say "Boo!" you’ll startle her and she might jump up in her seat (before she yells at you to quit it). Alarm clocks and barking dogs often startle people. The original meaning of startle, around 1300, was "to run back and forth," from the Old English word styrtan, "to leap up."

Keep Reading on Vocabulary.com

Vocabulary lists containing startle

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Few people who have been on the national stage this long retain an ability to startle.

From The Wall Street Journal • Nov. 24, 2025

But when she sees another dog, everything changes: she snarls, barks loud enough to startle a city block, and lunges with so much force it takes all my strength to hold her back.

From Salon • Aug. 18, 2025

While her decision to stand down as an MSP was obvious and much anticipated, it still has the capacity to startle.

From BBC • Mar. 12, 2025

“I’m a triple Aries,” she says with pride, sensing that it might startle me.

From Los Angeles Times • May 21, 2024

Even if he had been too preoccupied to hear the sounds of trucks or voices, Calamity would have, so quick to startle now that her kittens were close.

From "Bone Gap" by Laura Ruby