A person or thing that amazes; something that causes amazement or astonishment.
From amaze plus '-er,' a suffix creating an agent noun (one who does the action). Standard formation, though not as common as agent nouns from other verbs.
The word 'amazer' reminds us that English speakers have always needed a way to talk about amazing things—and they've tried nearly every suffix combination, with 'amazement' and 'wonder' eventually winning out in everyday speech.
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