The lake's placid surface reflected the surrounding pines, offering a tranquil scene for the hikers.
湖面平静如镜，倒映着周围的松树，为徒步者提供了一幅宁静的景象。
Which choice best defines “placid”?
C — Calm; peaceful; serene. “placid” means calm; peaceful; serene.
Which word means “calm; peaceful; serene”?
C — placid. “placid” means calm; peaceful; serene.
placid — calm; peaceful; serene. In Chinese: 平静的；温和的.
placid is pronounced /ˈplæsɪd/.
The lake's placid surface reflected the surrounding pines, offering a tranquil scene for the hikers. (湖面平静如镜，倒映着周围的松树，为徒步者提供了一幅宁静的景象。)
calm, serene, peaceful — all close in meaning to placid (calm; peaceful; serene).
turbulent, agitated — each the opposite of placid (calm; peaceful; serene).
Yes. placid is on the SAT Prep Easy list — mid-frequency academic words that do get tested. The Digital SAT does not test vocabulary in isolation; words like this one are tested through Words in Context questions, where you choose the word that completes a passage most logically and precisely.
plac (calm) + id → peaceful.