You might not think it to be so, but in its original form oakum was “off-combing.”
It referred to the hard, coarse strands of retted flax which were combed out before spinning, the tow.
The Old English word was acumba, considerably modified in spelling down through the years.
This tow, or “hards” as also called, was found to be useful in the calking of boats, and later the name was transferred to the strands of old rope, untwisted into its fibers and used for the same purpose.
