Geis
A surname with likely Germanic roots, probably tied to an old personal name built from the element gīs/gis, “spear” or “warrior.”
The #9,692 most common surname in the United States (2010 Census) — about 1 in every 92,245 Americans shares it.
Etymology
The most plausible explanation in the older surname literature is that Geis goes back to a short Germanic personal name such as Giso or a related form containing the element gis/geis. In that tradition, the root is linked to the idea of a spear, weapon, or fighting strength, rather than to the modern German word Geiß meaning "goat." The name may therefore have begun as a forename or nickname-based surname before becoming hereditary.
History
19th-century writers sometimes connected related forms with medieval German names and with a broader family of names built on gis/giso. German surname scholarship also shows that Geis can be confused in appearance with words for "goat," so some local forms may have been independently formed or reinterpreted. In the United States, the surname is relatively uncommon and likely reflects immigrant German or German-speaking ancestry.
Origin
Regions
Variant spellings
Fun fact
Older etymologists noticed that Geis sits near a whole cluster of similar German names, including Geis-, Gies-, Gisel-, and Geist-related forms, which makes it a classic example of how small spelling changes can hide an old name family.
From the historical record
“CASHMAN. From O. G. gast-mund, a powerful man (gast, potens) ; or from geis-mund, a strong man (gesus, vir fortis). Cf. the old German names Adalgis, Gisericus, Vitigis, Wetgisus, &c. It may also be from some Scotch name commencing with Mac. If the name be of German origin, we may have from it Cheeseman and…”
— Ludus Patronymicus; or, the etymology of curious surnames