What is the latin word for yourself?

Proprius, often with the appropriate possessive adjective: meus proprius "my own"; tuus proprius"your own"; suus proprius "his own."

Suus can also be used by itself to mean "his own," as in the phrase suum cuique "to each his own."

Of course, like all Latin adjectives, meus, tuus, suusand proprius take different forms depending on whether they're modifying a masculine, feminine or neuter noun (stated or implied), and depending on the function of that noun in the sentence (subject, direct object, indirect object, possessor, etc.)