Comparative form of mellow: more mellow(adjective)
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Use "mellower" in a sentence
"Blow says the package is suited to "mellower" environments, so expect at least a somewhat relaxing experience."
"The singer told Rolling Stone magazine that the sister record to the newly released No Line on the Horizon will be entitled Songs of Ascent and will have a 'mellower' vibe."
"While there's lots of talk in the media of a "mellower" Iron Mike, there have still been disquieting signs that Keenan is up to his old tricks in Calgary (Tanguay, Huselius, Nilson)."