Otherlink is similar to Copinglink in that it refers to a person who has voluntarily chosen a nonhuman identity, but for reasons other than coping.  Otherlinks are also known as 'linkers. Their chosen nonhuman identity is called their linktype, or 'type for short.
Linktypes have one or more purposes, which is why an Otherlink may change linktypes over time if the purpose(s) the linktype fulfilled has been accomplished or the need for it faded.
"It can be deeply integral to a person, or something fleeting that comes and goes. While hypothetically a 'link can be "dropped," it's more often that someone changes and evolves their link to better suit them than drop the identity entirely, which can be difficult depending on how integral the identity is to a person. "
- Nonhumanity and Nonsense, by Wix; an administrator of Alt+H 
The term was coined by several people in the Alt+H Discord server in January 2018. 
"'Otherlink' is a word that was coined in discussions of voluntary identities that weren’t constructed or chosen strictly for coping reasons, or for those who felt like the ‘coping’ part of the name undermined the identity or “broke the immersion” of some of it, so to speak.
So it’s a more generalized form of “copinglink,” in short. One that includes copinglinks but doesn’t necessitate that an identity be a coping-based one." - Victim of Changes, 26 January 2018 
There exist many otherlink labels such as ;
Copinglink/C'linker : A person who has chosen a nonhuman identity as a coping mechanism.
Funlink/F'linker : A person who has chosen a nonhuman identity for fun.
Supportlink/S'linker : A person who has chosen a nonhuman identity to feel a necessary emotional support which allows them to enter a specific mindset. For example, a supportlink may identify as a fictional character known for being brave, in order to feel more brave and act accordingly.
Aeslink : A person who has chosen a nonhuman identity in a purely aesthetical manner. Aeslinks adopt an aesthetic which ties to their linktype. For example, if they link with Angels they may invest in Angelcore fashion. In case their linktype is a fictional character, they may dye their hair the same color(s) and/or wear clothing that matches that character's overall aesthetic. It can also be a non-physical expression of their linktype's aesthetic such as managing a blog suiting their linktype's aesthetic.
See everything tagged #otherlink by Victim of Changes http://victiim-of-changes.tumblr.com/tagged/otherlink
- Victim of Changes "Otherlinkers are not "'kin but Voluntary"" January 26, 2018 http://victiim-of-changes.tumblr.com/post/170162038800/otherlinkers-are-not-kin-but-voluntary (Archived March 25, 2018 https://web.archive.org/web/20180325235532/http://victiim-of-changes.tumblr.com/post/170162038800/otherlinkers-are-not-kin-but-voluntary )
- February 5, 2018 http://victiim-of-changes.tumblr.com/post/170561701235/ey-is-there-a-word-for-voluntary-identity-that (Archived March 26 2018 at https://web.archive.org/web/20180326001232/http://victiim-of-changes.tumblr.com/post/170561701235/ey-is-there-a-word-for-voluntary-identity-that )
- http://victiim-of-changes.tumblr.com/post/170170259665/question-is-this-term-synonymous-with-copinglink ( Archived March 26, 2018 at https://web.archive.org/web/20180326001942/http://victiim-of-changes.tumblr.com/post/170170259665/question-is-this-term-synonymous-with-copinglink )