Highbred and Upper class

Highbred adjective - Of high birth, rank, or station.

Upper class and highbred are semantically related In some cases you can replace phrase "Upper class" with "Highbred", this terms are similar.

Upper class noun - The highest class in a society.

Highbred and upper class are semantically related in over topic. Sometimes you can use "Highbred" instead an adjective phrase "Upper class".