means The force or drive an object or effort builds up while in motion, making it harder to stop the longer it keeps going.

from Straight from Latin momentum, meaning 'movement' or 'a moving power' — itself a worn-down form of movimentum, from movere, 'to move' (the same root that gives us motion, motor, and emotion). It originally carried the sense of a tipping weight on a scale: the small thing that decides which way everything swings. Physics borrowed it formally in the 17th century to mean mass times velocity, and the rest of us borrowed it to describe how anything in motion tends to stay that way.