Geis is a German . Notable people with the surname include:
Bernard J. Geis (1909–2001), American editor and publisher Gemma Geis (born 1979), Catalan politician George J. Geis (), American Baptist minister and anthropologist Gerald Geis (1933-2022), American politician Gilbert Geis (1925–2012), American criminologist Irving Geis (1908–1997), American artist Jacob Geis (1890–1972), German theatre director, screenwriter and film producer Johannes Geis (born 1993), German footballer Norbert Geis (born 1939), German politician Paul Geis (1953–2019), Olympic athlete Richard E. Geis (1927–2013), American science fiction fan and writer
See also , in Irish, an idiosyncratic taboo, whether of obligation or prohibition, similar to being under a vow, with the plural having mystical connotations
Geiss (surname) Geist (surname)