broad muscle of the back

the pair of fan-shaped muscles across your middle and lower back that attach the arms to the spine. They work to pull your arms down and back, and give you good posture when they are toned. Rock climbing, swimming and rowing all use these muscles.

Back muscle used in one type of breast reconstruction.

The big "fan shaped" muscle in the middle and lower parts of the back. When these muscles are properly worked out they are what give a bodybuilder the sought after hourglass back (sexy V-shaped looked). The primary function of the lats is to puoll the arms back and downwards.