is a specific kind of: mass unit.

is a broader term that covers: grain | dram | ounce, oz. | lb, pound | half pound | quarter pound | stone | quarter | cwt, hundredweight, long hundredweight | cental, centner, cwt, hundredweight, quintal, short hundredweight | gross ton, long ton, ton | net ton, short ton, ton | kiloton | megaton ... show more.

is a part of: British Imperial System, British system, English system | avoirdupois, avoirdupois weight.