rack rent(n = noun.possession) - an extortionate rent;
is a kind of rent

bicycle rack, bomb rack, coat rack, dish rack, dress rack, economic rent, ground rent, luggage rack, magazine rack, music rack, peppercorn rent, pipe rack, plate rack, rack, rack and pinion, rack of lamb, rack railway, rack up, rent, rent collector, rent out, roof rack, ski rack, spice rack, tie rack, towel rack