Being the subject of a trend; currently popular, relevant or interesting.(adjective)
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Use "trending" in a sentence
"It was fun, too, to see my name trending on Twitter without having to kill anyone, say something inappropriate about Justin Bieber or quit my job and write a screed against the decline of mainstream journalism."
"Twitter actually keeps on the site a list of what it calls trending topics, taking a look at some of the most popular things people are tweeting about at the moment."
"Crawford's reporting resulted in her name "trending" on Twitter"