A large part of Donald Trump's shtick is to hurl cutting, oddly specific insults at his opponents.
In his book, Think Like a Billionaire, the same man who called Jeb Bush "low energy" and Marco Rubio a "lightweight" and a "choker" wrote these words:
HOW TO CRITICIZE SOMEONE
It's best to avoid criticizing anyone. Compliments work better, and sometimes silence is the best form of criticism available. I've known people who have said bad things to and about me who cannot take criticism themselves. Most people are one-way streets, and it's better not to spend your time dodging head-on traffic. If you stay silent, people will eventually make fools of themselves without your help at all. It's revenge the easy way.