Superlative form of groovy: most groovy.(adjective)
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Use "grooviest" in a sentence
"The latest was this production from Westinghouse and Jam Handy demonstrating how custom decorating your refrigerator doors is, like, the grooviest thing one could possibly do."
"Danger Mouse is about the grooviest guy around -- half of Gnarls Barkley, producer of Black Keys, member of the Broken Bells, creator of the Grey Album."
"Burman took advantage of Bhosle's vocal versatility and created songs for her that brought Western musical influences to Bollywood combining, say, congas with tablas or finding some of the grooviest psychedelic rock sounds."