Blackball rhymes with:
trackball, stickball, trackball, arenaball, basketball, butterball, cannonball, eyeball, fastball, fireball, football, handball, hardball, meatball, mothball, oddball, pinball, powerball, racquetball, screwball, snowball, softball, spaceball, spitball, stickball, tidball, trackball, volleyball
Blackball sounds like:
blackpool, blissful, blissfully