A lawnmower uses thin, replaceable blades with a hardened cutting edge and a cross-section defining an airfoil. Such blades are held by blade holding elements in a horizontally rotating mower blade assembly. The blade assembly and blade assembly housing are configured in a specialized cross-flow mower assembly to reduce grass leave tip damage, increase cut quality and overall aesthetic appeal, and create a cross-flow air current while consuming less power and providing a reduced environmental impact.