(1):

(v. t.) A wrinkle or crease in a piece of cloth, or in needlework.

(2):

(v. t. & i.) To draw into wrinkles or unsightly folds; to crease; as, to ruck up a carpet.

(3):

(n.) A heap; a rick.

(4):

(n.) The common sort, whether persons or things; as, the ruck in a horse race.

(5):

(v. i.) To cower; to huddle together; to squat; to sit, as a hen on eggs.

(6):

(n.) A roc.