To become congealed, solidify.
To change from a liquid to solid state, perhaps due to cold; called to freeze in nontechnical usage.
To coagulate, make curdled or semi-solid such as gel or jelly.
To make rigid or immobile.
To dilute; to add water to.
To simplify or oversimplify; to make easier; to make less difficult.
To make weaker, less effective.
To make less restrictive; to make more lenient.