Gilbert (given name)
Gilbert is a given name of Norman-French origin, itself from Germanic Gisilberht or Gisalberht. Original spellings included Gislebert, Guilbert and Gilebert. The first element, Gil-, comes from Germanic gīsil, meaning "shaft of an arrow" or gisal "pledge, hostage", while the second element, -bert comes from Germanic -behrt, short form of beraht, meaning "bright" or "famous". Another origin arises from Galwegian Gaelic in the name "Gille Brigte" meaning "follower of St Bridget" which is anglicised as "Gilbert". Gille Brigte or Gille Brighde is also the Gaelic for Oystercatcher, a sea bird associated with the story of St Bridget.
The name was introduced to England by the Normans where it was popular during the Middle Ages. That is the reason why the pronunciation Gil- [gil] reflects the Northern Norman one [gil], as opposed to Old French [dʒil] > French [ʒil] and explains the alternative spelling Guilbert with Guil- [gil].
Variant spellings have evolved throughout Europe, including the Romance language version, Gilberto, and the Latin version, Gilbertus. The diminutive, Gil, is popular as a given name or nickname. Gilbert, with variant spellings, is also used as a surname (see Gilbert (surname)).