It's used to describe something that is uncommon, exceptional, or unique.
The phrase has a slightly different connotation depending on the context:
* Positive: When used to describe a person, it often implies they are talented, skilled, or possess qualities that are hard to find.
* Neutral: It can simply mean something that is rare or unusual, without necessarily implying any positive or negative qualities.
* Negative: Sometimes, it can be used sarcastically to point out someone's eccentricity or strangeness.
Example Sentences:
* "She's a rara avis in the business world, with her innovative ideas and unwavering determination."
* "Finding a good mechanic these days is a rara avis."
* "He's such a rara avis, always doing things his own way."
Origin:
The phrase comes from the Latin phrase "rara avis in terris nigroque simillima cygno" which means "a rare bird in the land, and very like a black swan." This refers to the belief that black swans were extremely rare, and thus the phrase came to be used to describe anything uncommon or exceptional.