When the force acting on an object points at least partially in the direction of the motion the work done is considered to be negative

The answer for the missing word is "OPPOSITE"

Explanation:

Work done is the product of the force and displacements caused on an object. This work done can be either positive or negative. Work done is positive if the direction of force acting on an object is along the direction of motion of the object.

This is because, in this case the external force is helping the object to continue its state of motion.

However, in contrast, the workdone will be negative when the object stops or slows down the motion of the object if the force acting on the object is in completely opposite or partially opposite direction to the direction of motion of the object.

So, the answer is "OPPOSITE"