Jocelin

Jocelyn is a surname and first name. It is a unisex (male/female) name. Variants include Josalyn, Jocilyn, Joscelyn, Joscelin, Josceline, Joseline, Jocelin, Jocelyne, Jocelynne, Jocelynn, Joslin, Joslyn, Joclyn, Joselyn, Joselyne, 'Jocylen and Josslyn; people who have this name may find it is often misspelled by others. The name may derive from Josselin, a locality in Brittany, France, and was introduced to England after the Norman Conquest. It may also derive from the Germanic name Gauzlin, also spelled Gozlin or Goslin. It is Latinized as Iudocus or Judocus, from Breton Iodoc, diminutive of iudh (“lord”).

In French, the spelling "Jocelyn" is exclusively male. The female counterpart is spelled "Jocelyne".

The Irish name Oisdealbh is sometimes erroneously attributed to a translation of Jocelyn, to Gaelicize Jocelyn de Angulo's given name. In fact, MacOisdealbhaigh is the Gaelic translation of his brother Hostilo (or Hostilio) de Angulo's given name. It is Hostilo's descendants who would bear the surname Mac Oisdealbhaigh (son of Oisdealbh or Hostilo). The surname would later be anglicized to Costello, Costelloe, and Costellow.

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