What is a primitive character of a Galois groups of a finite cyclic extension of local fields?

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Let $K$ be a local field and $F/K$ be a cyclic extension of degree $n$, meaning that $n = [F:K]$ and $\operatorname{Gal}(F/K) \simeq C_n$ is cyclic.

In the proof of Lemma 2 of the paper "Euler Factors determine local Weil Representation" by Tim and Vladimir Dokchitser we considered a primitve character $\chi$ of $\operatorname{Gal}(F/K)$.

Question: What exactly is a primitive character? (Unfortunately, I was not able to find a proper definition somewhere.)

  • Does it has something to do with the Galois group being cyclic? Or is there a more general definition?
  • Do we need a Weil representation here (as this paper deals with them)?
  • Are these related with Dirichlet characters? (My professor mentioned them once but I still have no idea what they are.)

It would be really nice if you could respond to my questions. Thank you!