o·ver·run • v. / ˌōvərˈrən/ (-run·ning; past -ran; past part. -run) [tr.] 1. spread over or occupy (a place) in large numbers: the Mediterranean has been overrun by tourists. ∎  conquer or occupy (territory) by force: the northern frontier was overrun by invaders. ∎  move or extend over or beyond: let the text overrun the right-hand margin. ∎  run over or beyond (a thing or place): she overran third base. ∎  rotate faster than (another part of a machine): [as adj.] (overrunning) an overrunning clutch. 2. continue beyond or above (an expected or allowed time or cost): he mustn't overrun his budget.• n. / ˈōvərˌrən/ 1. an instance of something exceeding an expected or allowed time or cost: an unexpectedly large cost overrun in the program. ∎  the amount by which this happens: a $2.7 billion overrun on development and production. ∎  a surplus in manufacturing: production overruns by some OPEC members.2. the movement or extension of something beyond an allotted or particular position or space: the system acts as a brake to prevent cable overrun. ∎  a clear area beyond the end of an airport runway.3. the movement of a vehicle at a speed greater than is imparted by the engine.

overrun In ice cream manufacture, the percentage increase in the volume of the mix caused by the beating‐in of air. Optimum overrun, 70–100%. To prevent excessive aeration US regulations state that ice cream must weigh 4.5 lb per gallon (0.48 kg/L).