ruck1 [rʌk]
noun
1 a large number or quantity; mass, esp. of ordinary or undistinguished people or things

2 (in a race) a group of competitors who are well behind the leaders at the finish

3 (Rugby) a loose scrum that forms around the ball when it is on the ground

4 (Australian Rules football) the three players, two ruckmen and a rover, that do not have fixed positions but follow the ball closely
verb
5 [intransitive]
(Rugby) to try to win the ball by mauling and scrummaging
[ETYMOLOGY: C13 (meaning ``heap of firewood''): perhaps from Scandinavian; compare Old Norse hraukr rick1]


ruck2 [rʌk]
noun
1 a wrinkle, crease, or fold
verb
2 [usually foll by up] to become or make wrinkled, creased, or puckered
[ETYMOLOGY: 18th Century: from Scandinavian; related to Old Norse hrukka]


ruck3 [rʌk]
noun (prison slang)
a fight
[ETYMOLOGY: 20th Century: short for ruckus]