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English definition of “tester”


noun [C]     /ˈtes.tər/ US  /-tɚ/
a person or a machine that tests somethingTesting, checking and experimenting a small container of a product that you can try in order to see if you like itSamples and examples
(Definition of tester noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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