Blue-blooded is a term that typically refers to a person from a noble or aristocratic family. However, there are several antonyms for this expression, which can describe people of different backgrounds or social statuses. One antonym is "common-born," which refers to someone who is from a family with less prestigious lineage. Another antonym could be "working-class," describing those who have jobs in the trades rather than high positions in society. Finally, "humble" could also be an antonym for blue-blooded, as it refers to someone who is modest and unassuming, the opposite of the typical behavior of a person who comes from a privileged background.