Coalition (n): alliance, union, affiliation, bloc, federation, association,

 The coalition between the south Asian countries was not fruitful as it was expected.

Collide (v) strike. Run into, crash (into)

Collision (n): accident, strike, smash-up

The collision took place at 9 30 base on witness result 


Collapse (v): Suddenly fall down

Cave in , fall in, subside, fall down , slump

The stock market was collapsed