達 is a suffix that indicates plurality, used exclusively with nouns referring to people.
Usage rules
Register comparison
- たち: neutral, everyday usage
- 方: polite/honorific (先生方)
- ら: casual/rough (俺ら, 奴ら)
Usage
- Can indicate "X and others": 田中さんたち (Tanaka and the others)
- Not used for animals or objects in standard speech
- 友達 already contains たち but can still take たち (友達たち)