oddball

An eccentric or unusual person.

Miss Quinn thought that Oswald spoke Russian well in view of his lack of formal training; she found the evening uninteresting. Donovan, with whom she had a date later, testified that she told him that Oswald was “kind of an oddball.”

"She's different, mister. A real oddball, if you know what I mean. But your little girl would love her. All kids love the Doll Lady."

A deviant stimulus that appears among repetitive stimuli during an experiment, to trigger an event-related potential in the participant.

Exotic, not mainstream.

An oddball word processor, for example, might never be supported by such helpful tools as spelling checkers, indexing programs, footnote utilities,...