The ground or geological strata — the soil/rock layers beneath the surface; the physical ground.
この地域は地盤が弱く、液状化の危険があると報告された。
This area has weak ground and was reported to be at risk of liquefaction.
調査の結果、地盤は砂質であることがわかった。
Survey results showed that the ground is sandy.
The foundation or base that supports a building — the ground or footing important for construction stability.
地盤を強化するために杭を打つ工事を行った。
We carried out pile-driving work to reinforce the foundation.
高層ビルを建てるにはしっかりした地盤が必要だ。
A solid foundation is necessary to construct a high-rise building.
A power base or constituency — political or economic support that a person or organization relies on.
候補者は地盤を固めるために各地を回って支持集めをした。
The candidate toured various places to shore up his support base.
大企業は長年培った地盤があり、新規参入は難しい。
Large companies have long-established footholds, making new entry difficult.