Final answer:
The major hip stabilizer during mid stance of gait is the gluteus medius, which maintains posture and stabilizes the hip joint during the gait cycle.
Step-by-step explanation:
The question of what is the major hip stabilizer during mid stance of gait is primarily concerned with the muscles that provide stability to the pelvic girdle and lower limbs during the gait cycle. During mid stance, the primary hip stabilizer is the gluteus medius. This muscle assists with raising the knee at the hip and opening the thighs; it also maintains posture by stabilizing the iliotibial tract, which connects to the knee. The hip joint carries the weight of the body and requires strength and stability during standing and walking, and the gluteus medius contributes significantly to this stability.