"Bestiosexuality" was discussed briefly by Allen (1979), but never became widely established.
Ernest Bornemann (1990, cited by Rosenbauer, 1997) coined the separate term zoosadism for those who derive pleasure – sexual or otherwise – from inflicting pain on animals.
Although Krafft-Ebing also coined the term zooerasty for the paraphilia of exclusive sexual attraction to animals, as a value-neutral term.
Usage of zoosexual as a noun (in reference to a person) is synonymous with zoophile, while the adjectival form of the word – as, for instance, in the phrase "zoosexual act" – may indicate sexual activity between a human and a non-human animal.
The derivative noun "zoosexuality" is sometimes used by self-identified zoophiles in both support groups and on internet-based discussion forums to designate sexual orientation manifesting as romantic or emotional involvement with, or sexual attraction to, non-human animals.
Some zoophiles and researchers draw a distinction between zoophilia and bestiality, using the former to describe the desire to form sexual relationships with animals, and the latter to describe the sex acts alone.
The term zoophilia derives from the combination of two nouns in Greek: ζῷον (zṓion, meaning "animal") and φιλία (philia, meaning "(fraternal) love").
In general contemporary usage, the term zoophilia may refer to sexual activity between human and non-human animals, the desire to engage in such, or to the specific paraphilia (i.e., the atypical arousal) which indicates a definite preference for non-human animals over humans as sexual partners.
Zoosadism specifically is one member of the Macdonald triad of precursors to sociopathic behavior.
which he defined as a sexual attraction to animal skin or fur.
It may also be touched upon by sociology which looks both at zoosadism in examining patterns and issues related to sexual abuse and at non-sexual zoophilia in examining the role of animals as emotional support and companionship in human lives, and may fall within the scope of psychiatry if it becomes necessary to consider its significance in a clinical context. 18, February 2011) states that sexual contact with animals is almost never a clinically significant problem by itself; Additionally, zoophiles in categories 2, 3, and 8 (romantic zoophiles, zoophilic fantasizers, and regular zoophiles) are the most common, while zoophiles found in categories 6 and 7 (sadistic bestials and opportunistic zoophiles) are the least common.
Zoophilia may reflect childhood experimentation, sexual abuse or lack of other avenues of sexual expression.
Exclusive desire for animals rather than humans is considered a rare paraphilia, and sufferers often have other paraphilias The first detailed studies of zoophilia date from prior to 1910.