The term "rt. hon." is an abbreviation of the honorific phrase "right honorable" and is used to address or refer to certain government officials or dignitaries. Some synonyms for "rt. hon." are "Honorable", "Hon.", "The Right Honourable", and "The Rt. Honourable". These titles are typically used for high-ranking individuals such as cabinet ministers, members of parliament, and judges, who have demonstrated significant contributions to their field of work. These titles are often seen as a mark of respect and recognition of the individual's achievements, and are frequently used in formal or official situations.