unnatural
un-nat-u-ral
adjective
Not existing in nature; artificial, abnormal, or contrary to expected behaviour.
"The unnatural silence made everyone uneasy."
Thesaurus
Synonyms: kinky, atypical, freakish, abnormal, deviate, aberrant, antidromic, brachydactylic, brachydactylous, supernormal, defective, subnormal
Antonyms: natural, normal, unaffected