- Beef up - Build up - Fortify - Make firmer - Make stronger - Reinforce something - To make strong or stronger; to add strength to; as,
to strengthen a limb, a bridge, an army; to strengthen an obligation;
to strengthen authority.
- Cement - Combine into effective unit - Make firmer - Merge - Strengthen - Formed into a solid mass; made firm; consolidated. - To make solid; to unite or press together into a
compact mass; to harden or make dense and firm.
- Check - Check-up - Ratify - Substantiate swindle by a company - Verify - To make firm or firmer; to add strength to; to
establish; as, health is confirmed by exercise. - To strengthen in judgment or purpose.