What are words which by their utterance inflict injury or incite an immediate breach of peace called?

The terms that describe words which, when spoken, can cause injury or provoke an immediate breach of peace are known as "fighting words." This concept arises from the doctrine that certain types of speech are not protected under the First Amendment because they are likely to incite violence or a strong emotional reaction in the listener. The classic definition established in legal cases emphasizes that fighting words are those that are inherently likely to provoke a hostile reaction, making their utterance a potential catalyst for physical confrontation.

In contrast, incitements might refer generally to speech that encourages unlawful behavior, but they do not specifically denote words that immediately provoke violence. Hate speech entails expressions of prejudice or discrimination and is often subject to various legal interpretations but does not automatically fall under the category of provoking immediate violence. Obscene language, while sometimes devoid of First Amendment protections, relates more to obscenity and does not directly address the specific context of instigating immediate conflict or injury. Therefore, fighting words best captures the legal definition and contextual usage for speech that can instigate immediate breach of peace.