Displacement

[Sarah]

The process of extracting soluble substances from organicmaterial and the like, whereby a quantity of saturated solvent isdisplaced, or removed, for another quantity of the solvent. Pistondisplacement (Mech.), the volume of the space swept through, orweight of steam, water, etc., displaced, in a given time, by thepiston of a steam engine or pump.

[Sarah]

the nett distance travelled
consists of magnitude and direction

[Merna]

The action of moving something from its place or position.