crowd together, cluster together;〔虫などが〕swarm
- 広場には人々が密集していた
- The square was crowded with people.
- その辺は小住宅が密集している所だ
- In that area small houses 「are clustered [stand] close together.
- 巣箱の周りに蜜蜂が密集していた
- Bees were swarming around the beehive./The beehive was swarming with bees.
- 人口密集地域
- a densely populated district/a congested district [area]