Green’s Dictionary of Slang

dump v.

[SE dump, to throw down in a lump or mass]

1. [late 18C+] (orig. US, also dump off, dump out) to get rid of, to dispose of.

2. [mid-19C+] (US) to injure or kill by gunfire.

3. [20C+] to beat up; to knock down; thus dumping n., a beating.

4. [1940s] (US) to confess, to betray.

5. [1940s–70s] to murder.

6. [1940s+] to jilt, to terminate a relationship.

7. [1950s+] (also take a dump) to lose a game, esp. on purpose.

8. [1950s+] (orig. US campus, also dump it out) to defecate.

9. [1950s+] (drugs) to vomit through drug withdrawal sickness, or on first taking a drug; thus n. dumping.

10. [1960s] to dismiss from a job.

11. [1960s] (US prison) to reject a parole application.

12. [1960s] (US) to leave.

13. [1970s] to defeat, to ruin.

14. [1980s] (US black) to attack verbally.

In phrases

dump it out (v.)

see sense 8 above.

dump off (v.)

see sense 1 above.

dump one’s change (v.)

[2000s] (US black/drugs) to excrete bags of drugs after swallowing them when facing a police search.

dump out (v.)

see sense 1 above.

take a dump (v.)

see sense 7 above.

dump one’s load (v.)

see under load n.

SE in slang uses

In phrases

dump on (v.)

see separate entries.