🔼The name Gittite in the Bible
Gittite is not really a name but a feminine ethnonym. It denotes a female inhabitant of the Philistine city of Gath (גת). A male person from Gath would be a גתי (gitty; Gathite, although most translations read Gittite anyway), and that is an adjective.
Our "name" only occurs in three Psalm titles: Psalm 8:1, Psalm 81:1 and Psalm 84:1, in the phrase על־הגתית, meaning "upon the Gittite". What "the Gittite" exactly denotes isn't known.
🔼Etymology of the name Gittite
The name Gittite, as does the name Gath, comes from the root יגן, and is derived from the noun גת (gat), meaning winepress:
The name Gittite literally means Winepressish or From The Winepress. NOBSE Study Bible Name List explains this name as Belonging To Gath, and Jones' Dictionary of Old Testament Proper Names explains it as being a musical instrument. BDB Theological Dictionary reports that the Targum teaches the Gittite to be a lyre, but also submits the other explanations listed above.