As nouns the difference between distinctness and otherness
is that distinctness is the property or degree of being distinct while otherness is (uncountable) the quality of being different or distinct.
distinctness
English
Noun
(-)
The property or degree of being distinct.
otherness
English
Noun
(uncountable) The quality of being different or distinct.
(countable) The result or product of being different or distinct.
References
* [http://dictionary.reverso.net/spanish-english/otredad]
* [http://www.google.com/search?q=define%3A+otherness&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a]