Mailroom rhymes with:
ballroom, schoolroom, toolroom, backroom, ballroom, barroom, bathroom, bedroom, boardroom, bridegroom, classroom, cloakroom, courtroom, darkroom, elbowroom, headroom, livingroom, lunchroom, newsroom, playroom, restroom, schoolroom, stockroom, storeroom, sunroom, toolroom, washroom, workroom
Mailroom sounds like:
mehlhorn, melhorn, milhorn, milliron, mulhearn, mulheren, mulherin, mulhern, mulroney, mulrooney