Rule for feminine · die
-tät → die · no exceptions (0.6%)
Nouns ending in -tät are always feminine and take die - no exception has been found. The suffix comes from the Latin „-tas” and is used mainly for abstract concepts: die Qualität (quality), die Universität (university), die Realität (reality). It's a thin rule - only 0.6% of frequent nouns, 14 words total in our set - but because it's so consistent, it's worth learning without hesitation: see -tät, say die.