In Swedish we have the word tilltalsnamn (addressing name) which is one of the given names used when referring to a person. This name may or may not be the first among the given names. So a person with the full name Carl Johan Persson, say, may have the tilltalsnamn Johan. Is there a similar concept in English?
The classic Falsehoods Programmers Believe About Names list is always worth a good review.
Based on the comments, there is no direct equivalent in the English-speaking world to the concept of tilltalsnamn. In general, one's first name (ie. first given name, forename) is used for both address and for legal purposes, and any variation from that is an exception. Certainly, many people choose to go by a middle name, or another name, but there is no special status accorded to this name and no specific term that is universally used.
Something similar you may find in a CRM system, human resources file, or the like might be addressee or addressee name, the name that would be used to populate letters and mailings. For example, you would use Mike DeWine or R. Michael DeWine and not Richard DeWine or Richard M. DeWine if writing the current governor of Ohio.
Another common formulation is preferred name, i.e. the name one prefers to be known by. This need not have any relation to any part of the official name, however. Furthermore, someone might prefer different names in different scenarios— Mary Catherine Gallagher, MD might be
- Catherine Gallagher in day-to-day life
- M. Catherine Gallagher on her medical license
- Cat on her business card
- Katy on her nametag at her high school reunion
- Skeeter on her nametag at her sorority reunion
Example 6 would be a nickname, and many would consider 3 and 4 to be nicknames as well, but 1 and 2 would not be called nicknames, so it would be a poor mapping to the Swedish term.
If one must get down to this level of specificity, one must be specific when labeling: Name as it should appear on your name tag, Name as it should appear in the list of sponsors, etc.
A common phrase for this is chosen name.
Somebody's chosen name can be any of their legal names, a shortened version of one of those names, or even a nickname.
However, with respect to this question specifically, a chosen name would be restricted to one of the person's legal names. (I know of no English equivalent of that particular restriction.)
From "Chosen Name for Students" at Missouri State University (emphasis mine):
A student may choose a name other than their legal name to identify themselves at Missouri State University. A chosen name is different than the student’s legal name. Refer to the Chosen Name policy for more information.
Students can provide their chosen first and middle names in the Student tab of My Missouri State.
I imagine that choosing a first and middle name could apply to those people who have three more given names. (Otherwise, a chosen name commonly refers to just a single name that somebody would be greeted by.)
From the same school's "Chosen Name Policy" (emphasis mine):
It is the policy of Missouri State University that any student, faculty, or staff may choose to be identified within the University Community with a chosen name that differs from the individual’s legal first name.
Students, faculty, and staff who want to use a chosen name should initiate the process in the University’s web portal (My Missouri State). A person’s chosen name will appear instead of or in addition to the person’s legal first name in university-related systems and documents where it is technically feasible and where the use of the legal first name is not required by university business or legal need.
- Carl Johan Persson's chosen name is Johan.
- Gordon Matthew Thomas Sumner's chosen name is Sting.
- A woman named Dorothy might use the chosen name Dottie.
- A man named John might use the chosen name Jack.
Typically we would say that Johan is his nickname, which just happens to also be his middle name. Nickname is not limited to being part of the person's full legal name (their first, middle, and last name).
a familiar name given to a person or thing instead of (or as well as) the real name.