-core - a suffix denoting a fandom centered around an aesthetic or trend . Frequently used or referenced in alterhuman and nonhuman aesthetics and moodboards that contain images of things relating to requested identities (e.g., "angelcore" or "aliencore").
cladokin - an otherkin who identifies as more than one variant of a mythical creature . For instance, a cladokin could identify as multiple types of mythical horses, like a unicorn and a pegasus.
cladomythic - an otherkin who identifies specifically as a group (clade) of animalistic mythical creatures . See theriomythic for more information.
cladotherian - a therian whose identity is not species specific, and instead encompasses an entire clade of animals   . For instance a cladotherian could identify as the family Felidae (house cats, lynx, bobcats, cheetahs, etc.) instead of specifically a bobcat.
clinical lycanthropy - a rare psychiatric syndrome that where patients experience delusions that cause them to believe they are, are transforming into, or have previously transformed into a non-human animal  . The cause is debated, but may be due to abnormal brain function or psychosis resulting from varying mental illnesses. Clinical lycanthropy is typically not experienced by otherkin or therians.
co-fronting - when two or more members of a system are controlling the body at one time .
conceptkin - a subset of otherkin, who identify as a concept, instead of living beings .
constelic - someone who collects an identity/identities or multiple identities, of animals, fictional characters, mythological beings, etc. May or may not be done by choice and these identities can be dropped, hoarded, and have priority over each other .
contherianthropy - a therian whose nonhuman identity is integrated into their baseline personality to such a degree that the prominence of their human side and animal side do not change   . They may experience a constant, unchanging shift, or they may not experience shifts at all.
copinglink(er) - an individual who has chosen a nonhuman or fictional character identity as a coping mechanism for mental illness, trauma, or other stressor .