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The poundal is a unit o wechts an meisures at isnae a pairt o SI. It is a unit o force. It is a pairt o the absolute foot-pound-second system o units, a subsystem o English units inbrocht in 1879, an ane o several specialized subsystems o mechanical units uised as aids in calculations. It is defined as 1 lb·ft/s².

1 pdl = 0.138 254 954 376 N exactly