Here are some examples:
* defeat: to overcome or conquer (from "to do away with")
* deduce: to infer something from evidence (from "to lead down from")
* descend: to move downwards (from "to go down")
* detach: to separate (from "to take away")
* decompose: to break down (from "to put down")
However, "de" can also be part of a proper noun or place name, like:
* De Gaulle (French general and president)
* De Vries (Dutch surname)
* de Janeiro (part of Rio de Janeiro)
It's important to understand the context in which the word "de" is used to determine its meaning.