IPA: /sərˈpraɪzər/
KK: /sərˈpraɪzər/
A person who causes someone to feel surprised or astonished.
The magician was a great surpriser, always leaving the audience in awe.
Surpriser → It is formed from 'surprise' (from Old French *surprendre*, meaning to take over or seize) and '-er' (meaning a person who). A surpriser is a person who takes someone by surprise or catches them off guard.
Think of someone who 'takes over' ('surprendre') unexpectedly — that's why a surpriser is someone who catches you by surprise.