In the English language an English honorific is a title prefixing a person's name, e.g.: Miss, Ms, Mr, Sir, Mrs, Dr, Lady or Lord. They are not necessarily titles or positions that can appear without the person's name, as in the President, the Earl.
There are many forms of honorifics that are used when addressing the members of the nobility, clergy, or royalty, mostly in countries that are monarchies. These include "Your Majesty" and "Your Highness", which are often used when speaking with royalty, or "My lord/lady" to address a peer other than a Duke, who is referred to as "Your Grace".
Some honorifics distinguish the sex of the person being referred to. Some titles of the nobility and of professional honorifics such as Doctor or General are not gender specific because they were traditionally male-only professions, and women have simply adopted the associated titles.
Mx: (/ˈmɪx/) In October 2011, the title of Mx was added as an option for people who do not identify themselves as either male or female and, therefore, feel a gender specific title such as Mr or Miss is inappropriate and unsuitable for them. It is becoming more widely accepted as a gender-neutral title. 
Dr: (Doctor) for a person who has obtained any doctoral-level academic degree, such as the Doctor of Medicine (M.D.), Doctor of Osteopathic Medicine (D.O.), or Doctor of Philosophy (Ph.D.), but most often refers to a degree-holder in a medically related field, specifically a Physician or Surgeon (a.k.a. a medical 'doctor'). In the Commonwealth, holders of a Bachelor of Medicine and Bachelor of Surgery (MBBS or MBChB) are entitled to call themselves 'Doctor', though fully qualified surgeons are more often styled 'Mr.' (or female equivalent or gender-neutral common title).
Prof: (Professor) used generally for people teaching at the college level. Persons holding doctorate degrees outside the medical field are more likely to be referred to as "Prof" over "Dr" to prevent confusion with the common meaning of "Doctor" (because teaching at the college level generally requires a doctoral-level academic degree).