Sigfússon

Sigfússon is an Icelandic patronymic surname meaning "son of Sigfú." It is formed by adding the suffix -sson to the father's given name Sigfú; the corresponding feminine form is Sigfússdóttir. In Iceland, the vast majority of surnames are patronymics rather than fixed family names, so a Sigfússon may not share a direct paternal lineage with another person bearing the same surname if their fathers were named Sigfú.

The name Sigfú itself is of Old Norse origin, and Sigfússon therefore identifies a paternal line rather than a persistent family branch in the way hereditary surnames do in some other cultures. Because Icelandic practice emphasizes the father's (or sometimes the mother's) name rather than a fixed surname, the distribution of Sigfússon reflects naming patterns rather than a single genealogical clan.

Usage and distribution: The name is most common in Iceland and among Icelandic communities abroad, including North America and Europe. Icelandic naming conventions are regulated, with the Naming Committee evaluating new given names and certain surname formations. In contemporary practice, individuals or families may adopt a fixed hereditary surname for legal or cultural reasons, in which case Sigfússon could function as a family name beyond a single-generation patronymic.

Notable bearers: The surname has been borne by various Icelandic writers, scientists, and public figures. See also lists of Icelandic surnames for related forms and regional variations.