IPA: //ˈslændərəsnəs//
KK: /ˈslændərəsnəs/
The quality or state of making false spoken statements that damage someone's reputation.
The slanderousness of the accusations led to a public outcry.
Slanderousness → It is formed from "slander" (from Old French *esclandre*, meaning to defame or bring disgrace) and the suffix "-ous" (meaning full of) combined with "-ness" (meaning the state of). The word "slanderousness" refers to the state of being full of slander or defamation.
Think of the word 'slander' which means to defame someone, and remember that 'slanderousness' describes the state of being full of such defamation.