A disordered mass or heap of people, formed around an individual on whom others jump.
Origin
Late 19th century; earliest use found in Arthur's Home Magazine. From pig + pile.
pig-pile2
/ˈpɪɡpʌɪl/
USinformal
verb
1[with object]Of a person: to cause (a number of people) to lie on top of one another to form a pig pile. Of a number of people: to jump on top of (a person) to form a pig pile.
2[no object]Of a number of people: to jump on top of another to form a pig pile. Also (and recorded earliest) in hyperbolical use in Town Planning.
Origin
Late 19th century; earliest use found in Ballou's Monthly Magazine. From pig + pile.