preventive

Intended or used to prevent or hinder; acting as an obstacle.

Carried out to deter expected aggression by hostile forces.

Preventing or slowing the course of an illness or disease; prophylactic.

Something that prevents; an obstacle.

Something that prevents or slows the course of an illness or disease.

Serving to prevent or hinder; guarding against or warding off something, as disease, injustice, loss, etc.

That which goes before; an anticipation.

That which prevents; that which constitutes an effectual check or insurmountable obstacle.

Specifically, something taken, used, or done beforehand to ward off disease.

Also preventative.