Gaz

Diminutive of GARY or GARETH.

GARY   male   English
From an English surname which was derived from a Norman given name, which was itself originally a short form of names beginning with the Germanic element ger meaning "spear". This name was popularized in the late 1920s the American actor Gary Cooper (1901-1961), who took his stage name from the city of Gary in Indiana where his agent was born.
GARETH   male   Welsh, English (British), Arthurian Romance
Meaning unknown. It first appears in this form in Thomas Malory's 15th-century compilation of Arthurian legends 'Le Morte d'Arthur', in which Gareth was a Knight of the Round Table, the brother of Sir Gawain. Malory based the name on Gahariet, which was the name of a similar Arthurian character in French sources. It may ultimately have a Welsh origin, possibly related to gwaredd meaning "gentleness".
FULL FORMS
ENGLISH (BRITISH): Gareth
ENGLISH: Gary
EQUIVALENTS
ARTHURIAN ROMANCE: Gahariet, Gareth
WELSH: Gareth
OTHER FORMS
ANCIENT GERMANIC: Gero, Gervas, Gervasius
ANCIENT SCANDINAVIAN: Geirr
ENGLISH: Garey, Garry, Gervase, Jarvis, Jervis
FRENCH: Gervais, Gervaise
GERMAN: Gero, Gervas
ICELANDIC: Geir
ITALIAN: Gervasio
NORWEGIAN: Geir
POLISH: Gerwazy
PORTUGUESE: Gervásio
SPANISH: Gervasio