The act of becoming increasingly frumpy due to the intense frumpiness of those around you. This type of behavior is often observed in rural areas, such as rural New England, where dullness, plainness and a lack of fashion sense give way to an extremely high accepted level of frump.
Wow, I just took a trip back to New Hampshire and it was a total clusterfrump! I couldn't believe how much L.L. Bean catalogue action I saw!