partisan

partisan is a   Noun

Definition:

[1] An adherent to a party or faction; esp., one who is strongly and passionately devoted to a party or an interest. "The violence of a partisan." Macaulay. Both sides had their partisans in the colony. Jefferson.

[2] The commander of a body of detached light troops engaged in making forays and harassing an enemy.

[3] Any member of such a corps.

Synonyms: