A person who enjoys thrilling situations, or who engages in dangerous sports(noun)
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Use "thrill-seeker" in a sentence
"We had a few other methods we employed on the thrill-seeker shoplifters."
"A New Year's Eve thrill-seeker had the shock of her life last week during a bungee jump at Victoria Falls bridge."
"That kind of adrenaline rush can only be topped by diving with sharks at Rocky Bay on the Natal South Coast – in a cage, but also outside it if you're a true thrill-seeker!"