Prefixes are key morphemes in English vocabulary that begin words. A large number of English vocabulary words contain the prefix *se-*, which means "apart." Examples using this prefix include [*se*]parate, [*se*]cret and [*se*]lect. An easy way to remember that the prefix *se-* means "apart" is through the word [*se*]cure, for when you feel [*se*]cure you are "apart" from worrying or undue care about something potentially troubling.