Dead reckoning
Extrapolating a remote player's position from its last known position and velocity between packets — borrowed from the sailor's art of estimating position from heading and speed.
Updates about other players arrive only a few dozen times a second, so in between the client guesses: take the last position and velocity and keep moving the entity in a straight line. The name comes from maritime navigation — estimating where you are from heading, speed and elapsed time without a fix.
Games use it for remote players and vehicles, where you have no inputs to run proper client-side prediction on. When the next real packet disagrees, the entity is eased toward the truth rather than snapped to it. The idea long predates games and was formalised in the military's DIS simulation standard.