Mutilation or maiming is an act of physical injury that degrades the appearance or function of any living body, sometimes causing death.
Maiming, or mutilation which involves the loss of, or
incapacity to use, a bodily member, is and has been practised by many
societies with various cultural and religious significances, and is also
a customary form of physical punishment, especially applied on the principle of an eye for an eye.
The Araucanian warrior Galvarino suffered this punishment as a prisoner during the Spanish conquest of Chile.
In law, maiming is a criminal offence; the old law term for a special case of maiming of persons was mayhem, an Anglo-French variant form of the word.
Maiming of animals by others than their owners is a particular form
of the offence generally grouped as malicious damage. For the purpose of
the law as to this offence animals are divided into cattle, which
includes horses, pigs and asses, and other animals which are either
subjects of larceny at common law or are usually kept in confinement or for domestic purposes.
In Britain under the Malicious Damage Act 1861
the punishment for maiming of cattle was three to fourteen years penal
servitude; malicious injury to other animals is a misdemeanour
punishable on summary conviction. For a second offence the penalty is
imprisonment with hard labor for over twelve months. Maiming of animals
by their owner falls under the Cruelty to Animals Acts.
In times when even judicial physical punishment was still commonly allowed to cause not only intense pain and public humiliation
during the administration but also to inflict permanent physical
damage, or even deliberately intended to mark the criminal for life by docking or branding,
one of the common anatomical target areas not normally under permanent
cover of clothing (so particularly merciless in the long term) were the
William Laud, the Archbishop of Canterbury, had their ears cut off for those writings: in 1630 Dr. Alexander Leighton and in 1637 still other Puritans, John Bastwick, Henry Burton and William Prynne.
In Scotland one of the Covenanters, James Gavin of Douglas, Lanarkshire, had his ears cut off for refusing to renounce his religious faith. In Japan, Gonsalo Garcia and his companions were similarly treated.
Notably in various jurisdictions of colonial British North America
even relatively minor crimes, such as hog stealing, were punishable by
having one's ears nailed to the pillory and slit loose, or even cropped, a counterfeiter would be branded on top (for that crime, considered lèse majesté, the older mirror punishment was boiling in oil).
Independence did not render American justice any less bloody. For
example in the future state of Tennessee, an example of harsh 'frontier
law' under the 1780 Cumberland Compact took place in 1793 when Judge John McNairy
sentenced Nashville's first horse thief, John McKain, Jr., to be
fastened to a wooden stock one hour for 39 lashes, and have his ears cut
off and cheeks branded with the letters "H" and "T".
Tongue being cut is also a form of mutilation as this leads to bleeding to death in most cases with choking in the lungs. 
law, mutilation is, in certain cases, used as a punishment for crimes.
For example, thieves may be punished by having the right hand amputated.
Another example from a non-western culture is that of Nebahne Yohannes, an unsuccessful claimant to the Ethiopian imperial throne
who had his ears and nose cut off, yet was then freed. This form of
mutilation against unsuccessful claimants to thrones has been in use in
middle-eastern regions for thousands of years. To qualify as a king,
formerly, one had to exemplify perfection. Obvious physical deformities
such as missing noses, ears, or lips, are thereby sufficient
disqualifications. The victim in these cases is typically freed alive to
act (a) as an example to others, and (b) as no longer a threat.