arm or anterior limb[?] of a human or other primate, at where the appendage[?] terminates. This part of the limb is especially used in grasping and holding. The left hand is the mirror image of the right hand.
What constitutes a hand? Although many mammals and other animals have grasping appendages[?] similar in form to a hand, these are scientifically not considered to be so, and have other varying names, including paws[?]. Using the term hand is merely a scientific usage of anthropomorphization, to distinguish the terminations of the front paws from the hind ones. The only true hands appear in the mammalian order of primates. Hands must also feature opposable thumbs, as described later in the text.
Structure of the Hand The hand consists of a broad palm (metacarpus) with five digits, attached to the forearm by a joint called the wrist (carpus).
fingers on the hand are located at the outermost edge of the palm. These four digits can be folded over the palm, this allows for the holding of objects, and furthermore the grasping of small objects.
thumb (connected to the trapezium) is located on one the sides, parallel to the arm. The thumb can be easily rotated 90º, on a perpendicular level compared to the palm, unlike the fingers which can only be rotated approximately 45º. A reliable way of identifying true hands is from the presence of opposable thumbs. Other than opossums (Daubentoniidae), lemurs (Daubentoniidae) and the now extinct dinosaurs, this is a unique feature. Opposable thumbs are identified by the ability to be brought opposite to the fingers.
carpus or wrist account for 8; the metacarpus or palm contains 5; the remaining 14 are digital bones.
anatomical snuff box.
Articulation Also of note is that the articulation of the human hand is more complex and delicate than that of comparable organs in any other animals. Without this extra articulation, we would not be able to operate a wide variety of tools and devices. The hand can also form a fist[?], for example in combat, or as a gesture.
Common uses in English language I know it like the back of my hand - English phrase used to say that the subject knows the matter perfectly, as if it was part of their body, or that they were born with the knowledge. Related: Second hand.
Second hand - Similar to "I know it like the back of my hand," in that it is definitely known by the subject. Similar to something being described as second nature. Not to be confused with second-hand goods[?], which have already been used before, and are being resold.
A man may also describe somebody as his right hand man, which means that he relies heavily on this person.
A hand is also: