So there is some confusion where the name comes from and what it is supposed to mean. I read somewhere that the name was derived from carrying baskets of water at the end of a long pole. The more generally accepted meaning however is that of depicting a riding crop. Regardless of the origin and derivation, the move is common to almost all Tai-Chi styles.
At the end of the movement the left hand is in a palm outward push and the right hand held in the form of a hook, beak, or closed fist. Exceptions are the in Sun style and Wu style which finish with both hands open, palms outward.
Single Whip appears repeated several times in most styles of Tai-Chi. Twice in the Beijing standard 24 for instance, and ten times in traditional Yang style long form. It is easy to see how the appearance of this posture is almost a signature move of Tai-Chi.
The martial applications of Single Whip are many. Predominately it is used to lead or deflect the opponents hand or weapon past your body. There can be various strikes, throws, kicks, and changeups that can be initiated from this posture that are trained by different schools.
Using the Yang style as an example; Yang Chengfu’s outlines in his book”Tai Chi Chuan’s Practical Applications” (1931): “if an enemy attacks from the rear I would use my right hand to form a hook hand to dissolve the attack; at the same time the left palm would straighten out from the front to the left attacking the chest of the enemy…. The dissolving of the attack and the palm strike must be conducted simultaneously”.
Another Yang Chengfu book entitled “The Complete Volume of Tai Chi Chuan Usage” (1933) describes the use of the right hook hand and the left palm thusly: “If the enemy attacks from the rear, I would move my center to the left foot…. When the two hands wipe over to the left, the right hand forms a hook hand. The left palm moves inward with the center of the palm facing out. The waist and hips should relax as
the left palm attacks the chest of the enemy. This pattern of movements must be conducted at the same time.”
1902-1975