1.  fragmentation(n = noun.act) atomisation, atomization - separating something into fine particles;
is a kind of division
Derived form verb fragment₁

2.  fragmentation(n = noun.state) - the disintegration of social norms governing behavior and thought and social relationships;
is a kind of decomposition, disintegration
Derived form verb fragment₁

3.  fragmentation(n = noun.process) - (computer science) the condition of a file that is broken up and stored in many different locations on a magnetic disk; "fragmentation slows system performance because it takes extra time to locate and assemble the parts of the fragmented file"
is a kind of storage
Derived form verb fragment₁

4.  fragmentation(n = noun.event) - the scattering of bomb fragments after the bomb explodes;
is a kind of blowup, detonation, explosion
Derived form verb fragment₁

   the act or process of separating something into small pieces or fine particles. [WordNet 1.5]

fragmentation, n. the process or an instance of breaking into fragments.

Idiom:
fragmentation bomb a bomb designed to break up into small rapidly-moving fragments when exploded.

fragmentation bomb, fragmentation grenade