(quantum field theory) A physical force of attraction between very closely separated objects, due to random quantum fluctuations of the electromagnetic field in a vacuum; it is inversely proportional to the fourth power of the distance of separation

plural of tidal force

A force that completely balances the weight of an object at rest.

(American spelling) Work which one is compelled to perform against one's will, especially in a condition of involuntary servitude as a prisoner or slave.

(British spelling) Alternative spelling of forced labor

The hypothetical principle that animates all living organisms. / An impulse or influence that gives something life or vitality.

Alternative spelling of life force

The collective group of people who are available for employment, whether currently employed or unemployed (though sometimes only those unemployed people who are seeking work are included).

(mechanics) A polygonal figure the sides of which are vectors representing several forces acting simultaneously upon one point, so that the vector necessary to make the figure closed is the resultant of those forces.

(mechanics) A parallelogram, two adjacent sides of which are vectors having the same initial point and representing two forces acting simultaneously upon this point, such that the resultant of the forces is given by the diagonal of the parallelogram that passes through this point.