jam band
noun
plural jam bands
: a band (especially a rock band) whose performances are distinguished by frequent and often lengthy jazzlike improvisation
—sometimes hyphenated when used before another noun
Blues Traveler is part of the new wave of jam bands … that play long, long shows and inspire fan devotion reminiscent of the Grateful Dead.—
Dean Johnson
This Friday, the jam band Phish—which … remains uniquely regarded for its improvisational prowess and zealous, wayfaring fans—will arrive in New York City for thirteen shows …—
Amanda Petrusich
… Moon Taxi embodies the best of the jam band aesthetic: positive, bright, challenging and fun.—
Ann Powers
Gov't Mule brought a refreshing oomph to … the jam-band scene.—
Matt Wake
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Merriam-Webster unabridged



