Feth

Feth is the name of the spirit that possesses the nal-wood trees on the planet Tanith, allowing them to move their position. The Tanith First-And-Only (Ghosts, as they call themselves), the only surviving people from Tanith, use it as an explicative. After the Ghosts are called to and stationed at Verunhive, it is combined with the native word 'gak' to form such expressions as 'fething gakhead'.