get together

1.  Accumulate, gather, as in Go get all the firewood together: [c. 1400]
2.  Come together, assemble, as in Let's get together next week. The variant get together with means "meet with someone," as in I can't get together with them today but I'll have time next week. [Late 1600s]
3.  Arrive at an agreement, as in The jury was unable to get together on a verdict.
4.  get something or oneself together. See under get one's act together.

Definition: gather, accumulate
Antonyms: disperse, distribute, divide, scatter, separate

The noun has one meaning:

Meaning #1: a small informal social gathering
  Synonym: meeting

The verb get together has 4 meanings:

Meaning #1: get people together
  Synonyms: assemble, gather

Meaning #2: get together socially or for a specific purpose
  Synonym: meet

Meaning #3: work together on a common enterprise of project
  Synonyms: collaborate, join forces, cooperate

Meaning #4: become part of; become a member of a group or organization
  Synonyms: join, fall in