A means of establishing; something that strengthens, supports, or corroborates. Obsolete.

Strengthening. of bodily organs. Obsolete.

Physical strengthening. Obsolete. rare.

The process of strengthening or making firm.

The action of strengthen, v. (in various senses); the fact of being strengthened. Also: an instance of this.

an act or means of raising to a higher tone; a strengthening or improvement.