Middle-class and Old line

Middle-class adjective - Occupying a socioeconomic position intermediate between those of the lower classes and the wealthy.

Old line and middle-class are semantically related In some cases you can replace phrase "Old line" with "Middle-class", this phrases are similar.

Middle-class and old line are semantically related in commonplace topic. You can use "Middle-class" instead an adjective phrase "Old line".