Here are examples of the word/phrase "truncate" used in a sentence and paraphrased in a sentence...
If it's too large to get through, all you have to do is truncate it.
If it's too large to get through, all you have to do is minimize it.
You can use a blade to truncate the rope.
You can use a blade to shorten the rope.
That comic book character has the power to truncate his size and increase his size.
That comic book character has the power to minimize his size and increase his size.
Other Examples...