to hang loose without stiffness; to bend down, as flexible bodies; to be loose, yielding, limp.-to droop; to grow spiritless; to lose vigor; to languish; as, the spirits flag; the streugth flags.-to let droop; to suffer to fall, or let fall, into feebleness; as, to flag the wings.-to enervate; to exhaust the vigor or elasticity of.-that which flags or hangs down loosely.-a cloth usually bearing a device or devices and used to indicate nationality, party, etc., or to give or ask information; -- commonly attached to a staff to be waved by the wind; a standard; a banner; an ensign; the colors; as, the national flag; a military or a naval flag.-a group of feathers on the lower part of the legs of certain hawks, owls, etc.-a group of elongated wing feathers in certain hawks.-the bushy tail of a dog, as of a setter.-to signal to with a flag; as, to flag a train.-to convey, as a message, by means of flag signals; as, to flag an order to troops or vessels at a distance.-an aquatic plant, with long, ensiform leaves, belonging to either of the genera iris and acorus.-to furnish or deck out with flags.-a flat stone used for paving.-any hard, evenly stratified sandstone, which splits into layers suitable for flagstones.-to lay with flags of flat stones.