1874 W. Crookes Pract. Handbk. Dyeing 654 Another important operation is ‘crabbing’. Before stuffs can be dyed, all dirt, grease, and the dressing used by the weaver, must be completely removed. The pieces are generally first passed through hot water. They are next treated with hot lyes of soap, carbonate of soda, and liquid ammonia.

1892 Prof. Hummel (letter) Crabbing is the operation of passing a thin woollen or union fabric in a state of tension, and in the open-width, through boiling water, and at once wrapping it on a roller, where it is subjected to considerable pressure. The primary object of crabbing is to prevent subsequent wrinkling of the cloth, due to unequal contraction. A secondary object is to give the cloth a particular finish, so that the operation is now frequently used for all-wool and all-cotton cloth.

1885 J. J. Hummel Dyeing Textile Fabrics 112 The boiling water in the crabbing trough.

1892 Machine Maker's Advt. Makers of all kind of machinery for dyeing, etc...viz. crabbing, singeing, scouring, washing..machines.