—v.i. 1. to fail to maintain a desired pace or to keep up; fall or stay behind: After five minutes of hard running, some of them began to lag. 2. to move or develop slowly, as toward a goal or objective, or in relation to an associated factor (often fol. by behind): to lag behind in production. 3. to delay or fail in reaching full development: The factory lags regularly in making its quota. 4. to hang back; linger; delay: The old friends lagged because they wanted to talk some more. 5. to decrease, wane, or flag gradually, as in intensity: Interest lagged as the meeting went on. 6. Marbles.to throw one's shooting marble toward a line (lag line) on the ground in order to decide on the order of play.
7. Billiards,Pool.string (def. 17b).
—v.t. 1. to fail to keep up with: The industry still lags the national economy. 2. Obs.to cause to lag.
—n. 1. a lagging or falling behind; retardation.
2. a person who lags behind, is the last to arrive, etc.
3. an interval or lapse of time: There was a developmental lag in the diffusion of ideas. 4. Mech.the amount of retardation of some motion.
5. Elect.the retardation of one alternating quantity, as current, with respect to another related alternating quantity, as voltage, often expressed in degrees.
6. Marbles,Billiards.the act of lagging.