The term 'lycanthropy' was the term commonly used by members of AHWW before the term 'therianthropy' began to be used. The group also used the term 'were' (a shortened version of werewolf) as a term to refer to all non-humans. It was used due to it being non-specific about species.
However, in folklore, lycanthropy is the ability or power of a human being to undergo transformation into a wolf. The term comes from the Greek word lykánthropos, a mix of 'lýkos' (wolf) and 'ánthrōpos' (man).
There is also a mental illness known as clinical lycanthropy. This is where a patient believes they are transforming, have transformed, or can transform into an animal. It is separate from therianthropy.