Thy words have upholden him that was falling, and thou hast strengthened the feeble knees.
to strengthen a limb, a bridge, an army; to strengthen an obligation; to strengthen authority
But the Fed could use its postmeeting statement to strengthen expectations that it is on course to raise rates for the first time since the Great Recession when the committee next meets in September.
Meaning of strengthened for the defined word.
Grammatically, this word "strengthened" is a verb, more specifically, a verb form.