IPA: //ˌæk.jʊˈzeɪ.ʃən//
KK: /ˌæk.jəˈzeɪ.ʃən/
A statement that someone has done something wrong or illegal. It involves claiming that a person is guilty of a fault or crime.
The accusation against him was proven to be false.
Accusation is formed from "ad-" (meaning to) and "causare" (meaning to cause or to make a case). The word refers to the act of making a case against someone, implying that they have done something wrong.
Think of 'making a case against someone' — 'ad-' means to, and 'causare' means to cause or make a case.