The meaning of thall was kept very secret for years, and was used as an inside joke to torment members of the djent community. Some speculated it was the name of their debut LP release, but this proved to be incorrect as Vildhjarta put out an album named Måsstaden instead. Others speculated it was onomatopoeic, in the same manner as the word "djent"; used to describe the twangy thall sound of Vildhjarta's heavily-distorted extended range guitars. This also proved to be inaccurate.

The origins of the word thall were revealed by Calle and Daniel - they were slurring the word Thrull, and after, took it upon themselves to share the hilarious distortion of the word all over the internet. The word's popularity was hugely propagated by their rabid fanbase who would embrace thall and frequently leave comments consisting of just the word alone all over Facebook and YouTube.

Thus, thall has no true meaning, but has become a word unto itself.
Vildhjarta means "Wild Heart".