The *scalar space* of a motion is the arc length along the curve it traces out. The *scalar time* of a motion is the travel time along the route it traces out.

The *time rate* is “The rate at which something takes place over time.” The *space rate* is the rate at which something takes time over a route.

A quantity at a timepoint of a timeline is *instantaneous*. A quantity at a point of a baseline is *placepoint*.

*Speed* is the time rate of motion, the scalar space per unit of scalar time. The speed at a timepoint of time is called the *instantaneous* speed, which equals the differential scalar space per differential scalar time or the magnitude of the instantaneous velocity.

*Pace* is the space rate of motion, the scalar time per unit of scalar space. The pace at a point of space is called the *placepoint *pace, which equals the differential scalar space per differential scalar time or the magnitude of the placepoint lenticity. A gradient is the space rate of change of a function or scalar field.

*Displacement* is the directed distance or vector difference between two points in three-dimensional space. *Dischronment* is the directed duration or vector difference between two instants in three-dimensional time.

*Velocity* is the time rate of change of dischronment, which consists of the speed and direction of motion. The average velocity is the displacement per scalar time of motion. The velocity at a timepoint is called the *instantaneous* velocity, and is the differential displacement per differential scalar time. The instantaneous velocity equals the time rate of change of the displacement.

*Lenticity *is the space rate of change of dischronment, which consists of the pace and direction of motion. Lenticity is the rate of progress on a trajectory or path. The average lenticity is the dischronment per scalar space of motion. The lenticity at a point of space is called the *placepoint *lenticity, and is the differential dischronment per differential scalar space. Cf. velocity.

*Acceleration* is the time rate of change of velocity with respect to time. *Relentation* is the space rate of change of lenticity with respect to distance.

The first moment of mass is mass times distance. The *momentum* is the time rate of change of the first moment of mass. The first moment of vass is vass times duration. The space rate of change of the first moment of vass is the *levamentum*, from Latin for alleviate.

*Power* is the time rate of change of energy. *Force* is the space rate of change of energy.