A kunya is a component of an Arabic name, a type of epithet, in theory referring to the bearer's first-born son or daughter. By extension, it may also have hypothetical or metaphorical references, e.g. in a nom de guerre or a nickname, without literally referring to a son or a daughter. Use of a kunya implies a familiar but respectful setting.
A kunya is expressed by the use of abū (father) or umm (mother) in a genitive construction, i.e. "father of" or "mother of" as an honorific in place of or alongside given names in the Arab world and the Islamic world more generally.
Abū or Umm precedes the son's or daughter's name, in a genitive construction (ʼiḍāfa). For example, the English equivalent would be to call a man "Father of John" if his eldest son is named John. Use of the kunya normally signifies some closeness between the speaker and the person so addressed, but is more polite than use of the first name. The kunya is also frequently used with reference to politicians and other celebrities to indicate respect.
A kunya may also be a nickname expressing the attachment of an individual to a certain thing, as in Abu Bakr, "father of the camel foal", given because of this person's love for camels.
When also using a person's own birth name, the kunya will precede the proper name. Thus: abū Māzin Maħmūd, for "Mahmud, the father of Mazen" (as, for example, for Mahmoud Abbas). In Classical Arabic, but not in any of the spoken dialects, abū can change into the forms abā and abī (accusative and genitive, respectively), depending on the position of the kunya in the sentence.