Verb:AIM
AIM can be used to target the area of a body when AMBUSHing or firing a ranged weapon. Whereas AIM (location) is the proper syntax. Possible locations include: head, neck, right arm, left arm, right leg, left leg, right hand, left hand, chest, abdomen, back, right eye, left eye. Typing AIM CLEAR will clear your default aiming preference. AIM RANDOM will also clear it. One may also type AIM LIST to get a list of possible locations in-game.
When AIMing ranged weapons while not hidden, the Perception skill provides a bonus to strike at an AIMed body location of a specified target. When hidden, Perception and Ambush skill are equally factored into the chance to hit the desired location.
For more information regarding the factors determining the success of AIMing melee weapons, see the AMBUSH (verb) article.