Kēlen is a constructed language created by Sylvia Sotomayor. It is an attempt to create a truly alien language by violating a key linguistic universal — namely that all human languages have verbs. In Kēlen, relationships between the noun phrases making up the sentence are expressed by one of four relationals. Despite this, Kēlen is an expressive and intelligible language; texts written in Kēlen have been translated into other languages by several people other than the creator of the language, as may be seen here. In this interview Sotomayor states that she aims for Kēlen to be naturalistic apart from its verblessness, and that to achieve this she employs the principle "change one thing and keep everything else the same".
In its concultural setting, Kēlen is spoken by an alien species (the Kēleñi).
Kēlen is mentioned prominently by Sarah L Higley in her book Hildegard of Bingen's Unknown Language: An edition, translation and discussion (Palgrave Macmillan 2007, The New Middle AgesISBN 1-4039-7673-2, ISBN 978-1-4039-7673-4) where she discusses Lingua Ignota in the context of constructed languages up to the present day. She describes it as an example of the desire for originality in contemporary conlanging, by virtue of its verbless grammar, and notes that it is a prominent example of a conlang created by a woman. She also says that "fellow conlangers consider Kēlen to be efficient, elegant, strange and innovative, and its writing system is greatly admired." Kēlen is also discussed at length in this paper by M. Yu. Sidorova and O.N. Shuvalova, Several glossed examples are given.
At the third Language Creation Conference David J. Peterson awarded the Smiley Award to Kēlen, describing it as "an engineered language with the soul of an artistic language". He explains that while its experimental structure is in many ways similar to an engineered language, the amount of linguistic and concultural detail given by Sotomayor (including inflection of the relationals, three different scripts, and information on Kēleñi culture and society such as a calendar and a method of divination) make it a fully fledged artistic project rather than a simple experiment. Kēlen also comes with its own writing system, which bears a superficial resemblance to Devanagari.