preliminary

(noun) a minor match preceding the main event. Synonyms: prelim.

(noun) something that serves as a preceding event or introduces what follows. Synonyms: overture, prelude. Examples: "Training is a necessary preliminary to employment." "Drinks were the overture to dinner."

(adj) denoting an action or event preceding or in preparation for something more important; designed to orient or acquaint with a situation before proceeding. Example: "A preliminary investigation."