weirdo
n. countablen. a person who behaves in a strange or unusual way. You use this word when someone's actions or appearance seem very different from what is normal.
n. a person whose appearance or behaviour is considered strikingly odd or unconventional. Often carries a derogatory or dismissive tone.
Some weirdo was shouting at the pigeons in the park.
He didn't want to be seen as the office weirdo, so he kept his unusual hobbies to himself.
While the term is often used to marginalise those who do not conform, some subcultures have reclaimed it as a badge of pride for their unique perspectives.
From weird + -o (“person with characteristic”). The earliest documented usages date to the early 1950s in the United States. The similar Scottish word "weirdie" (also referring to an odd, unconventional person) is attested from earlier, in 1887.
Often used with the indefinite article 'a' or 'some' to refer to a stranger.