swears
v.v. to use offensive or rude language, often when you are angry. It can also mean to make a serious promise that something is true.
v. to use profane or offensive language, typically as an expression of anger or frustration; alternatively, to make a solemn or formal declaration of truth.
He always swears when he stubs his toe.
The witness swears to tell the truth before giving her testimony to the court.
While some people use profanity for emphasis in casual conversation, others find it offensive when a speaker swears in a professional environment.
Often takes the preposition 'at' when directed toward a person, or 'to' when making a promise.
He swears me when he is angryHe swears at me when he is angryWhen directed at a person, the verb requires the preposition 'at'.