This term is used to signify legal sufficiency, in contradistinction to mere regularity. “An official sale, an order, judg-ment, or decree may be regular,—the whole practice in reference to its entry may be correct,—but still invalid, for reasons going be-hlnd the regularity of its forms.” Sharpleigh v. Surdam, 1 Flip. 487, Fed. Cas. No. 12.71L
Source: Black's Law Dictionary 2nd Ed (1910)
