Fullstop

Though a symbol, can end anyone's life,

It can give our life such a turn which can be as sharp as a knife.

Spherical in shape,

Can be measured by a tape.

A small punctuation but has a heavy weight,

It can give one a happy or sad fate.

It describes the end of a stage,

Or the end of a notorious reign to freedom from a cage.

It may not appear on the top,

But mind it, its fullstop.