Definition of koshers:
(adj) :
(Judaism) Fit for use or consumption, in accordance with Jewish law (especially relating to food).
(adj) :
Observant of the rules of kashrut (of a person or establishment).
(adj) :
(figuratively, by extension) In accordance with standards or usual practice.
(adv) :
In a kosher manner; in accordance with kashrut.
(v) :
(transitive) To kasher; to prepare (for example, meat) in conformity with the requirements of the Jewish law.