From konstig + -het. <span class="searchmatch">konstighet</span> c weirdness (negative clauses) problem, issue inga konstigheter ― no problems <span class="searchmatch">konstighet</span> in Svenska Akademiens ordböcker...
<span class="searchmatch">konstighets</span> indefinite genitive singular of <span class="searchmatch">konstighet</span>...
konstigheters indefinite genitive plural of <span class="searchmatch">konstighet</span>...
konstigheternas definite genitive plural of <span class="searchmatch">konstighet</span>...
konstighetens definite genitive singular of <span class="searchmatch">konstighet</span>...