The word Gittish signifies belonging to Gath. It probably denotes either a musical instrument or a kind of music derived from Gath, where David sojourned for a time during the persecution of Saul, 1 Samuel 27:1-7. The word Gath also signifies in Hebrew a winepress. Hence not a few have supposed that it denotes either an instrument or a melody used in the vintage. It is prefixed to Psalms 8:1-9; 81:1- 16; 84:1-12, all of which requires an animated strain of music.
These dictionary topics are from American Tract Society Bible Dictionary published in 1859. Public Domain, copy freely.
Rand, W. W. "Entry for 'GITTITH'". "American Tract Society Bible Dictionary".