/ ˈstɑːtl; NAmE ˈstɑːrtl/ verb
to surprise sb suddenly in a way that slightly shocks or frightens them :
[ vn ]
I didn't mean to startle you.
The explosion startled the horse.
I was startled by her question.
[ vn to inf ]
It startled me to find her sitting in my office.
➡ note at frighten , surprise
► star·tled / ˈstɑːtld; NAmE ˈstɑːrtld/ adjective :
She looked at him with startled eyes.
He looked startled.
She jumped back like a startled rabbit.
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WORD ORIGIN
Old English steartlian kick, struggle , from the base of start . The early sense gave rise to move quickly, caper (typically said of cattle), which led to the sense cause to react with fear (late 16th cent.).