Costco rhymes with:
trustco, atco, bartko, dutko, huntco, mallightco, ontko, patco, petko, putco, ratko, sitko, trustco, tutko, vetco, voytko, witco, wometco
Costco sounds like:
c-codes, c.d.s, cactus, caddick, caddies, caddock, caddyshack, cadets, cadieux, cadiz, cads, cahoots, casados, cascade's, cascades, cascades', caskets, cassettes, cassidy's, castaways, castes, casts, cat's, catch, catches, catchy, cates, cathodes, cathy's, catija, cats, caustic, cautious, cdc, cds, cedes, cetec, cetus, cetus's, chad's, chaddock, chadick, chadwick, chadwick's, chaidez, chaotic, chastise, chastises, chataqua, chateaux, chatichai, chatichai's, chatihachi, chatihachi's, chats, chattahoochee, chattahoochee's, chatz, chatz', chatz's, chautauqua, cheats, checketts, checkouts, cheektowaga, cheetahs, chests, chicots, chides, chidsey, chits, chittick, chudzik, chujitsuya, chustz, chutes, chykatka, cicadas, cites, citgo, citic, cities, cities', city's, coast's, coasts, coat's, coates, coats, cockatoos, codag, code's, codes, codesa, coeds, cohosts, coitus, cookouts, coots, cosatu's, costas, costs, cotes, cotija, cots, cottage, cottages, couchettes, cousteau's, couts, coutts, coyotes, cushitic, custis, cutesy, cutouts, cuts, cutshaw, cutts, cycads, cystic, cysts, cytotech, cytotechs