i Register
In some senses, twerp is marked as UK, colloquial, US. Watch for register when choosing this word.
noun
A fool, a twit.
Now you've broken it, you twerp!
There's many an airman just finishin' his time. There's many a twerp signing on.
A small or puny person; one regarded as insignificant, contemptible.
Get out of my way, you little twerp!
A person who can be bullied playfully, or easily teased. Sometimes used as a pet-name (often for a younger sibling).