Left field is a phrase commonly used in English to describe something that is unexpected or unusual. It has its origins in baseball, where the left field is the farthest field from home plate and often requires a long throw to reach. Synonyms for left field include out of the ordinary, eccentric, peculiar, offbeat, quirky, idiosyncratic, unconventional, off-the-wall, bizarre, and strange. These words all suggest something that is not a typical or expected part of a situation or conversation. Left field can also be used to describe a person who is difficult to understand or predict, hence the use of synonyms like unconventional and eccentric.