Bluegrass rhymes with:
eelgrass, piepgras, shortgrass, snodgrass, tallgrass, eelgrass, piepgras, sassafras, shortgrass, snodgrass, tallgrass
Bluegrass sounds like:
balcerowicz, balcerzak, bellcore's, blackrock, blasier's, blazers, bleachers, blockers, bolger's, bulgaria's