Boulders rhymes with:
folders, holder's, holders, holders', molders, shoulders, bewilders, bondholders, bondholders', builder's, builders, builders', cardholders, childers, childres, debtholders, elders, elders', fielder's, fielders, folders, freeholders, gilder's, guilder's, guilders, holder's, holders, holders', homebuilder's, homebuilders, householders, infielders, junkholders, landholders, molders, noteholders, officeholders, outfielders, policyholder's, policyholders, policyholders', rebuilders, selders, shareholder's, shareholders, shareholders', shipbuilders, shoulders, stakeholders, stockholders, stockholders', unitholders, welders, wilder's, worlders
Boulders sounds like:
balderas, baldric, baldrige, balladur's, beladur's, bellwethers, bewilders, bladders, blowdries, blowdryers, blowtorch, blowtorches, builder's, builders, builders'