From Longman Dictionary of Contemporary Englishrattlesnakerat‧tle‧snake /ˈrætlsneɪk/ noun [countable] 
HBAa poisonous American snake that shakes its tail to make a noise when it is angry
HBAa poisonous American snake that shakes its tail to make a noise when it is angryExamples from the Corpus
rattlesnake• A man in his 20s had been bitten by a rattlesnake.• One guy kissed a rattlesnake on the lips, twice, and still lost.• She'd as soon trust a rattlesnake when he looked at her that way!• However, when fighting against another rattlesnake it does not use its poison fangs.• And one guy got bit by a baby rattlesnake.• I had rattlesnakes shake their tails at me.• As soon as we opened the car doors we could hear the sizzling of the rattlesnakes. 