[TA] intrinsic muscle of palm; origin, by two heads, the transverse head from the shaft of the third metacarpal and the oblique head from the front of the base of the second metacarpal, the trapezoid and capitate bones; insertion, medial side of base of proximal phalanx of thumb; action, adducts thumb; nerve supply, ulnar. SYN: musculus adductor pollicis [TA], adductor muscle of thumb.
