Synonyms for Groovy (same or very similar meaning)
WordNet sense 1 (very good):
bully, dandy, great, keen, neat, nifty, peachy, smashing, swell, corking, cracking, slap-up, bang-up, not bad
WordNet sense 2 (having desirable or positive qualities especially those suitable for a thing specified):
good
WordNet sense 3 ((British informal) very chic):
swagger
WordNet sense 4 (being or in accordance with current social fashions):
fashionable
From the ODE community, based on WordNet
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