Dictionary.com
Thesaurus.com
Synonyms

weirdo

American  
[weer-doh] / ˈwɪər doʊ /

noun

Informal.

plural

weirdos
  1. an odd, eccentric, or unconventional person.

  2. a psychopath, especially a dangerous or vicious one; psycho.

    They caught the weirdo who attacked the children.


weirdo British  
/ ˈwɪədəʊ, ˈwɪədɪ /

noun

  1. informal a person who behaves in a bizarre or eccentric manner

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Usage

What does weirdo mean? A weirdo is a person who behaves in ways that are considered odd or unconventional.Weirdo is based on the adjective weird, which most commonly means strange, odd, peculiar, or bizarre. Weirdo is very informal. It can be used both negatively as an insult and positively as a compliment, depending on how you feel about someone else’s weird behavior.Much less commonly, weirdo can be used as an informal term for a person considered a dangerous psychopath.Example: My dog keeps licking the wall—what a weirdo!

Etymology

Origin of weirdo

First recorded in 1950–55; weird + -o

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

As for Nice Guy, they have this chicken Parmesan but I’m a weirdo, I eat the chicken Parmesan without the Parmesan.

From Los Angeles Times

But also eccentric, loner, rogue, oddball—even weirdo.

From The Wall Street Journal

He should have known this was a bad idea, as if they were going to get anything useful off of some weirdo they found deep in the darkest bowels of the internet.

From Literature

“A strange little pack of a burned coyote, a weirdo human who likes coyotes, and an opossum.”

From Literature

The other benefit of being obsessed with the Christmas singles was that it helped you find the other weirdos.

From Salon