A hit man, especially being in some organization.
An official person who carries out the capital punishment of a criminal.
A person who is employed as an armed guard, enforcer, or mercenary and who is prepared to use gunplay or similar violent methods in order to assert the interests of his or her employer.
A person who is employed to advance the interests of his or her employer, especially in a vigorous manner using such methods as political lobbying, legal advocacy, or persuasion.