Definition of fronts:
(n) :
The foremost side of something or the end that faces the direction it normally moves.
(n) :
The side of a building with the main entrance.
(n) :
A field of activity.
(n) :
A person or institution acting as the public face of some other, covert group.
(n) :
(meteorology) The interface or transition zone between two airmasses of different density, often resulting in precipitation. Since the temperature distribution is the most important regulator of atmospheric density, a front almost invariably separates airmasses of different temperature.
(n) :
(military) An area where armies are engaged in conflict, especially the line of contact.