Literally, "Your" (n.) - 'an English word that is used when one person is talking to another and they want to refer to the person they are talking to in a 1st person point of view' + "Mother" (n.) - 'an English word that describes a female of a certain species that is or was capable of sexual reproduction at some point in their lives and exercised that aspect of their lives, and caused the creation and growth of a fetal offspring in their womb, egg, or pouch'; therefore, "Your" + "Mother" = the mother of a creature that a person who speaks English is referring to in a 1st person point of view. Don't you just love these literal definitions to just irritate the hell out of people?