Definition of "humping"

The foreign ladies, in their simple, tasteful, fresh attire, innocent of the humpings and bunchings, the monstrosities and deformities of ultra-fashionable bad taste, beamed with cheerfulness, friendliness, and kindliness.

1974, Isabella Bird, Six Months in the Sandwich Islands, amongst the Palm Groves, Coral Reefs and Volcanoes

As for sex, every man in the county knew of the famous thirty-minute humpings available from one of the 'girls' who worked out of the rear rooms of Angels Motel.

2007, Rod Wallsmith, Booze, Blood and Justice