The Sanskrit word karna means ear and the prefix "a" means near to or towards. Dhanur means bow-shaped, curved or bent. The "bow" here referred to is a bow as in "bow and arrow." Literally we could translate this as the near-the-ear bow posture but because of the obvious appearance of the posture we'll call it the shooting bow posture.
"Having caught the toes of the feet with both hands and carried them to the ears by drawing the body like a bow, it becomes Dhanura-asana." The Hatha-Yoga-Pradipika I.27.
Shooting Bow Posture (Akarna-asana) Instruction:
Sit on the floor with the legs together and extended straight out in front. Keep the back straight, shoulders level and head straight. Place the hands, palms down, flat on top of the thighs then inhale deeply.
Exhale and reach down and loop the forefinger of the right hand around the big toe of the right foot and grasp the left foot with the left hand.
Inhale and pull the right foot back placing the big toe next to the right ear. Straighten the back as much s possible and hold the posture for the duration of the inhale breath.
Exhale and return to the seated position of step #1 then repeat the posture on the opposite side.
While performing this posture imagine yourself as an archer with your gaze focused on a target and the arrow gracefully and steadily being pulled back in the bow. Hold the posture as steady as an archer would hold an arrow aimed at its target. Return the foot to the floor gently. This simple technique will help cultivate focused and unwavering attention.
This posture should be held for a minimum of 30 seconds and can be extended to up to several minutes. Repeat at least twice with each leg.
Reverse the hands and feet so that that the right hand pulls the left foot to the left ear and vice versa. The foot gets pulled under the outstretched arm.